645601248 has 144 divisors (see below), whose sum is σ = 2011398480. Its totient is φ = 195514368.

The previous prime is 645601189. The next prime is 645601301. The reversal of 645601248 is 842106546.

645601248 is a `hidden beast` number, since 6 + 4 + 5 + 601 + 2 + 48 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 139711 + ... + 144257.

It is an arithmetic number, because the mean of its divisors is an integer number (13968045).

Almost surely, 2^645601248 is an apocalyptic number.

645601248 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645601248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1005699240).

645601248 is an abundant number, since it is smaller than the sum of its proper divisors (1365797232).

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

645601248 is a wasteful number, since it uses less digits than its factorization.

645601248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4609 (or 4598 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 645601248 is about 25408.6844995958. The cubic root of 645601248 is about 864.2806444279.

The spelling of 645601248 in words is "six hundred forty-five million, six hundred one thousand, two hundred forty-eight".