51172132894 has 4 divisors (see below), whose sum is σ = 76758199344. Its totient is φ = 25586066446.

The previous prime is 51172132849. The next prime is 51172132901. The reversal of 51172132894 is 49823127115.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 49823127115 = 5 ⋅9964625423.

It is a self number, because there is not a number n which added to its sum of digits gives 51172132894.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12793033222 + ... + 12793033225.

It is an arithmetic number, because the mean of its divisors is an integer number (19189549836).

Almost surely, 2^51172132894 is an apocalyptic number.

51172132894 is a deficient number, since it is larger than the sum of its proper divisors (25586066450).

51172132894 is a wasteful number, since it uses less digits than its factorization.

51172132894 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25586066449.

The product of its digits is 120960, while the sum is 43.

The spelling of 51172132894 in words is "fifty-one billion, one hundred seventy-two million, one hundred thirty-two thousand, eight hundred ninety-four".