90721600 has 42 divisors (see below), whose sum is σ = 223235774. Its totient is φ = 36288000.

The previous prime is 90721597. The next prime is 90721607. The reversal of 90721600 is 612709.

It can be written as a sum of positive squares in 3 ways, for example, as 9144576 + 81577024 = 3024^2 + 9032^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90721607) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 26751 + ... + 29950.

Almost surely, 2^90721600 is an apocalyptic number.

It is an amenable number.

90721600 is an abundant number, since it is smaller than the sum of its proper divisors (132514174).

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

90721600 is a wasteful number, since it uses less digits than its factorization.

90721600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56723 (or 56708 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 90721600 is about 9524.7887115673. The cubic root of 90721600 is about 449.3349847951.

The spelling of 90721600 in words is "ninety million, seven hundred twenty-one thousand, six hundred".