90733721 has 32 divisors (see below), whose sum is σ = 108864000. Its totient is φ = 74850048.

The previous prime is 90733717. The next prime is 90733723. The reversal of 90733721 is 12733709.

It is not a de Polignac number, because 90733721 - 2² = 90733717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90733723) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 379520 + ... + 379758.

It is an arithmetic number, because the mean of its divisors is an integer number (3402000).

Almost surely, 2^90733721 is an apocalyptic number.

It is an amenable number.

90733721 is a deficient number, since it is larger than the sum of its proper divisors (18130279).

90733721 is a wasteful number, since it uses less digits than its factorization.

90733721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 353.

The product of its (nonzero) digits is 7938, while the sum is 32.

The square root of 90733721 is about 9525.4249773960. The cubic root of 90733721 is about 449.3549952697.

The spelling of 90733721 in words is "ninety million, seven hundred thirty-three thousand, seven hundred twenty-one".