91649570 has 16 divisors (see below), whose sum is σ = 170658360. Its totient is φ = 35395584.

The previous prime is 91649563. The next prime is 91649573. The reversal of 91649570 is 7594619.

It can be written as a sum of positive squares in 4 ways, for example, as 77141089 + 14508481 = 8783^2 + 3809^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (91649573) 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, 157727 + ... + 158306.

Almost surely, 2^91649570 is an apocalyptic number.

91649570 is a deficient number, since it is larger than the sum of its proper divisors (79008790).

91649570 is a wasteful number, since it uses less digits than its factorization.

91649570 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316069.

The product of its (nonzero) digits is 68040, while the sum is 41.

The square root of 91649570 is about 9573.3781916312. The cubic root of 91649570 is about 450.8618380696.

The spelling of 91649570 in words is "ninety-one million, six hundred forty-nine thousand, five hundred seventy".