91420564 has 6 divisors (see below), whose sum is σ = 159985994. Its totient is φ = 45710280.

The previous prime is 91420541. The next prime is 91420591. The reversal of 91420564 is 46502419.

It can be written as a sum of positive squares in only one way, i.e., 90098064 + 1322500 = 9492^2 + 1150^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11427567 + ... + 11427574.

Almost surely, 2^91420564 is an apocalyptic number.

It is an amenable number.

91420564 is a deficient number, since it is larger than the sum of its proper divisors (68565430).

91420564 is a wasteful number, since it uses less digits than its factorization.

91420564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22855145 (or 22855143 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 91420564 is about 9561.4101470442. The cubic root of 91420564 is about 450.4860000339.

The spelling of 91420564 in words is "ninety-one million, four hundred twenty thousand, five hundred sixty-four".