813656492953920 has 1344 divisors, whose sum is σ = 3687556523800320. Its totient is φ = 169071400673280.

The previous prime is 813656492953883. The next prime is 813656492953949. The reversal of 813656492953920 is 29359294656318.

813656492953920 is a `hidden beast` number, since 8 + 1 + 3 + 6 + 5 + 6 + 49 + 29 + 539 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 376135252 + ... + 378292268.

Almost surely, 2^{813656492953920} is an apocalyptic number.

813656492953920 is a gapful number since it is divisible by the number (80) 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 813656492953920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1843778261900160).

813656492953920 is an abundant number, since it is smaller than the sum of its proper divisors (2873900030846400).

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

813656492953920 is a wasteful number, since it uses less digits than its factorization.

813656492953920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2157080 (or 2157045 counting only the distinct ones).

The product of its (nonzero) digits is 755827200, while the sum is 72.

The spelling of 813656492953920 in words is "eight hundred thirteen trillion, six hundred fifty-six billion, four hundred ninety-two million, nine hundred fifty-three thousand, nine hundred twenty".