91421499779 has 8 divisors (see below), whose sum is σ = 91941525312. Its totient is φ = 90901638720.

The previous prime is 91421499751. The next prime is 91421499781. The reversal of 91421499779 is 97799412419.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91421499779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91421499479) 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, 1175567 + ... + 1250919.

It is an arithmetic number, because the mean of its divisors is an integer number (11492690664).

Almost surely, 2^91421499779 is an apocalyptic number.

91421499779 is a deficient number, since it is larger than the sum of its proper divisors (520025533).

91421499779 is a wasteful number, since it uses less digits than its factorization.

91421499779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82237.

The product of its digits is 10287648, while the sum is 62.

The spelling of 91421499779 in words is "ninety-one billion, four hundred twenty-one million, four hundred ninety-nine thousand, seven hundred seventy-nine".