51897219091 has 16 divisors (see below), whose sum is σ = 55154476800. Its totient is φ = 48738630528.

The previous prime is 51897219083. The next prime is 51897219103. The reversal of 51897219091 is 19091279815.

It is not a de Polignac number, because 51897219091 - 2³ = 51897219083 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51897219391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5384865 + ... + 5394493.

It is an arithmetic number, because the mean of its divisors is an integer number (3447154800).

Almost surely, 2^51897219091 is an apocalyptic number.

51897219091 is a deficient number, since it is larger than the sum of its proper divisors (3257257709).

51897219091 is a wasteful number, since it uses less digits than its factorization.

51897219091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14718.

The product of its (nonzero) digits is 408240, while the sum is 52.

The spelling of 51897219091 in words is "fifty-one billion, eight hundred ninety-seven million, two hundred nineteen thousand, ninety-one".