813420020 has 192 divisors, whose sum is σ = 2148249600. Its totient is φ = 252564480.

The previous prime is 813420019. The next prime is 813420053. The reversal of 813420020 is 20024318.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 813419974 and 813420001.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11142704 + ... + 11142776.

It is an arithmetic number, because the mean of its divisors is an integer number (11188800).

Almost surely, 2^813420020 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 813420020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1074124800).

813420020 is an abundant number, since it is smaller than the sum of its proper divisors (1334829580).

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

813420020 is a wasteful number, since it uses less digits than its factorization.

813420020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238 (or 236 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 813420020 is about 28520.5192799851. The cubic root of 813420020 is about 933.4798599317.

Adding to 813420020 its reverse (20024318), we get a palindrome (833444338).

The spelling of 813420020 in words is "eight hundred thirteen million, four hundred twenty thousand, twenty".