997477355520 has 832 divisors, whose sum is σ = 3885286176000. Its totient is φ = 241648533504.

The previous prime is 997477355507. The next prime is 997477355531. The reversal of 997477355520 is 25553774799.

997477355520 is a `hidden beast` number, since 9 + 9 + 7 + 4 + 7 + 73 + 5 + 552 + 0 = 666.

It is a super-2 number, since 2×997477355520² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 272607451 + ... + 272611109.

Almost surely, 2^997477355520 is an apocalyptic number.

997477355520 is a gapful number since it is divisible by the number (90) 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 997477355520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1942643088000).

997477355520 is an abundant number, since it is smaller than the sum of its proper divisors (2887808820480).

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

997477355520 is a wasteful number, since it uses less digits than its factorization.

997477355520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3743 (or 3715 counting only the distinct ones).

The product of its (nonzero) digits is 83349000, while the sum is 63.

The spelling of 997477355520 in words is "nine hundred ninety-seven billion, four hundred seventy-seven million, three hundred fifty-five thousand, five hundred twenty".