91213636 has 24 divisors (see below), whose sum is σ = 172209240. Its totient is φ = 42112512.

The previous prime is 91213627. The next prime is 91213657. The reversal of 91213636 is 63631219.

It can be written as a sum of positive squares in 4 ways, for example, as 38564100 + 52649536 = 6210^2 + 7256^2 .

It is a junction number, because it is equal to n+sod(n) for n = 91213598 and 91213607.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9051 + ... + 16258.

It is an arithmetic number, because the mean of its divisors is an integer number (7175385).

Almost surely, 2^91213636 is an apocalyptic number.

It is an amenable number.

91213636 is a deficient number, since it is larger than the sum of its proper divisors (80995604).

91213636 is a wasteful number, since it uses less digits than its factorization.

91213636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25383 (or 25381 counting only the distinct ones).

The product of its digits is 5832, while the sum is 31.

The square root of 91213636 is about 9550.5830188528. The cubic root of 91213636 is about 450.1458556003.

The spelling of 91213636 in words is "ninety-one million, two hundred thirteen thousand, six hundred thirty-six".