55716397991 has 8 divisors (see below), whose sum is σ = 57548463744. Its totient is φ = 53886504960.

The previous prime is 55716397969. The next prime is 55716397999. The reversal of 55716397991 is 19979361755.

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

It is a cyclic number.

It is not a de Polignac number, because 55716397991 - 2²⁶ = 55649289127 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55716397999) 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, 490970 + ... + 593703.

It is an arithmetic number, because the mean of its divisors is an integer number (7193557968).

Almost surely, 2^55716397991 is an apocalyptic number.

55716397991 is a deficient number, since it is larger than the sum of its proper divisors (1832065753).

55716397991 is a wasteful number, since it uses less digits than its factorization.

55716397991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1086361.

The product of its digits is 16074450, while the sum is 62.

The spelling of 55716397991 in words is "fifty-five billion, seven hundred sixteen million, three hundred ninety-seven thousand, nine hundred ninety-one".