51616031 has 4 divisors (see below), whose sum is σ = 51886464. Its totient is φ = 51345600.

The previous prime is 51616009. The next prime is 51616043. The reversal of 51616031 is 13061615.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51616031 is a prime.

It is a super-2 number, since 2×51616031² = 5328429312385922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51615988 and 51616006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51612031) 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, 134930 + ... + 135311.

It is an arithmetic number, because the mean of its divisors is an integer number (12971616).

Almost surely, 2^51616031 is an apocalyptic number.

51616031 is a deficient number, since it is larger than the sum of its proper divisors (270433).

51616031 is a wasteful number, since it uses less digits than its factorization.

51616031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270432.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 51616031 is about 7184.4297616443. The cubic root of 51616031 is about 372.3301473269.

Adding to 51616031 its reverse (13061615), we get a palindrome (64677646).

The spelling of 51616031 in words is "fifty-one million, six hundred sixteen thousand, thirty-one".