91561223602 has 4 divisors (see below), whose sum is σ = 137341835406. Its totient is φ = 45780611800.

The previous prime is 91561223597. The next prime is 91561223647. The reversal of 91561223602 is 20632216519.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 72618931441 + 18942292161 = 269479^2 + 137631^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22890305899 + ... + 22890305902.

Almost surely, 2^91561223602 is an apocalyptic number.

91561223602 is a deficient number, since it is larger than the sum of its proper divisors (45780611804).

91561223602 is a wasteful number, since it uses less digits than its factorization.

91561223602 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45780611803.

The product of its (nonzero) digits is 38880, while the sum is 37.

The spelling of 91561223602 in words is "ninety-one billion, five hundred sixty-one million, two hundred twenty-three thousand, six hundred two".