90475729920 has 880 divisors, whose sum is σ = 352781584848. Its totient is φ = 22083010560.

The previous prime is 90475729913. The next prime is 90475729933. The reversal of 90475729920 is 2992757409.

90475729920 is a `hidden beast` number, since 9 + 0 + 47 + 572 + 9 + 9 + 20 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 25365021696 + 65110708224 = 159264^2 + 255168^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 289059684 + ... + 289059996.

Almost surely, 2^90475729920 is an apocalyptic number.

90475729920 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 90475729920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (176390792424).

90475729920 is an abundant number, since it is smaller than the sum of its proper divisors (262305854928).

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

90475729920 is a wasteful number, since it uses less digits than its factorization.

90475729920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408 (or 381 counting only the distinct ones).

The product of its (nonzero) digits is 2857680, while the sum is 54.

The spelling of 90475729920 in words is "ninety billion, four hundred seventy-five million, seven hundred twenty-nine thousand, nine hundred twenty".