51147997 has 8 divisors (see below), whose sum is σ = 52099200. Its totient is φ = 50204544.

The previous prime is 51147989. The next prime is 51148037. The reversal of 51147997 is 79974115.

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 51147997 - 2³ = 51147989 is a prime.

It is a super-2 number, since 2×51147997² = 5232235194224018, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51147907) 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, 12333 + ... + 15949.

It is an arithmetic number, because the mean of its divisors is an integer number (6512400).

Almost surely, 2^51147997 is an apocalyptic number.

It is an amenable number.

51147997 is a deficient number, since it is larger than the sum of its proper divisors (951203).

51147997 is a wasteful number, since it uses less digits than its factorization.

51147997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3875.

The product of its digits is 79380, while the sum is 43.

The square root of 51147997 is about 7151.7827847328. The cubic root of 51147997 is about 371.2013471520.

The spelling of 51147997 in words is "fifty-one million, one hundred forty-seven thousand, nine hundred ninety-seven".