90921768 has 32 divisors (see below), whose sum is σ = 259776960. Its totient is φ = 25977600.

The previous prime is 90921767. The next prime is 90921827. The reversal of 90921768 is 86712909.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (90921767) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 270433 + ... + 270768.

It is an arithmetic number, because the mean of its divisors is an integer number (8118030).

Almost surely, 2^90921768 is an apocalyptic number.

It is an amenable number.

90921768 is an abundant number, since it is smaller than the sum of its proper divisors (168855192).

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

90921768 is a wasteful number, since it uses less digits than its factorization.

90921768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541217 (or 541213 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 42.

The square root of 90921768 is about 9535.2906615373. The cubic root of 90921768 is about 449.6652127179.

The spelling of 90921768 in words is "ninety million, nine hundred twenty-one thousand, seven hundred sixty-eight".