51479993 has 4 divisors (see below), whose sum is σ = 52575360. Its totient is φ = 50384628.

The previous prime is 51479983. The next prime is 51479999. The reversal of 51479993 is 39997415.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51479993 - 2⁶ = 51479929 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (47), and also a Moran number because the ratio is a prime number: 1095319 = 51479993 / (5 + 1 + 4 + 7 + 9 + 9 + 9 + 3).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51479999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 547613 + ... + 547706.

It is an arithmetic number, because the mean of its divisors is an integer number (13143840).

Almost surely, 2^51479993 is an apocalyptic number.

It is an amenable number.

51479993 is a deficient number, since it is larger than the sum of its proper divisors (1095367).

51479993 is a wasteful number, since it uses less digits than its factorization.

51479993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1095366.

The product of its digits is 306180, while the sum is 47.

The square root of 51479993 is about 7174.9559580530. The cubic root of 51479993 is about 372.0027580055.

The spelling of 51479993 in words is "fifty-one million, four hundred seventy-nine thousand, nine hundred ninety-three".