51212591 has 8 divisors (see below), whose sum is σ = 51654624. Its totient is φ = 50772960.

The previous prime is 51212587. The next prime is 51212599. The reversal of 51212591 is 19521215.

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 51212591 - 2² = 51212587 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51212591.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51212599) 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, 80846 + ... + 81476.

It is an arithmetic number, because the mean of its divisors is an integer number (6456828).

Almost surely, 2^51212591 is an apocalyptic number.

51212591 is a deficient number, since it is larger than the sum of its proper divisors (442033).

51212591 is a wasteful number, since it uses less digits than its factorization.

51212591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1201.

The product of its digits is 900, while the sum is 26.

The square root of 51212591 is about 7156.2972967869. The cubic root of 51212591 is about 371.3575428635.

The spelling of 51212591 in words is "fifty-one million, two hundred twelve thousand, five hundred ninety-one".