51496991 has 16 divisors (see below), whose sum is σ = 64680000. Its totient is φ = 40741344.

The previous prime is 51496979. The next prime is 51496997. The reversal of 51496991 is 19969415.

It is a de Polignac number, because none of the positive numbers 2^k-51496991 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51496997) 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, 1316 + ... + 10233.

It is an arithmetic number, because the mean of its divisors is an integer number (4042500).

Almost surely, 2^51496991 is an apocalyptic number.

51496991 is a deficient number, since it is larger than the sum of its proper divisors (13183009).

51496991 is a wasteful number, since it uses less digits than its factorization.

51496991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11583 (or 11569 counting only the distinct ones).

The product of its digits is 87480, while the sum is 44.

The square root of 51496991 is about 7176.1403971773. The cubic root of 51496991 is about 372.0436969327.

The spelling of 51496991 in words is "fifty-one million, four hundred ninety-six thousand, nine hundred ninety-one".