813963648 has 128 divisors (see below), whose sum is σ = 2354976000. Its totient is φ = 248113152.

The previous prime is 813963643. The next prime is 813963649. The reversal of 813963648 is 846369318.

It is a tau number, because it is divible by the number of its divisors (128).

It is a hoax number, since the sum of its digits (48) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a junction number, because it is equal to n+sod(n) for n = 813963597 and 813963606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (813963643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 209661 + ... + 213507.

It is an arithmetic number, because the mean of its divisors is an integer number (18398250).

Almost surely, 2^813963648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 813963648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1177488000).

813963648 is an abundant number, since it is smaller than the sum of its proper divisors (1541012352).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

813963648 is a wasteful number, since it uses less digits than its factorization.

813963648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3912 (or 3900 counting only the distinct ones).

The product of its digits is 746496, while the sum is 48.

The square root of 813963648 is about 28530.0481597911. The cubic root of 813963648 is about 933.6877692398.

The spelling of 813963648 in words is "eight hundred thirteen million, nine hundred sixty-three thousand, six hundred forty-eight".