91192078646 has 4 divisors (see below), whose sum is σ = 136788117972. Its totient is φ = 45596039322.

The previous prime is 91192078643. The next prime is 91192078697. The reversal of 91192078646 is 64687029119.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91192078643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22798019660 + ... + 22798019663.

It is an arithmetic number, because the mean of its divisors is an integer number (34197029493).

Almost surely, 2^91192078646 is an apocalyptic number.

91192078646 is a deficient number, since it is larger than the sum of its proper divisors (45596039326).

91192078646 is a wasteful number, since it uses less digits than its factorization.

91192078646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45596039325.

The product of its (nonzero) digits is 1306368, while the sum is 53.

The spelling of 91192078646 in words is "ninety-one billion, one hundred ninety-two million, seventy-eight thousand, six hundred forty-six".