51616 has 12 divisors (see below), whose sum is σ = 101682. Its totient is φ = 25792.

The previous prime is 51613. The next prime is 51631. The reversal of 51616 is 61615.

51616 = T₁₈₄ + T₁₈₅ + T₁₈₆.

It can be written as a sum of positive squares in only one way, i.e., 41616 + 10000 = 204^2 + 100^2 .

It is a super-2 number, since 2×51616² = 5328422912, which contains 22 as substring.

It is a nialpdrome in base 9.

It is a junction number, because it is equal to n+sod(n) for n = 51593 and 51602.

It is not an unprimeable number, because it can be changed into a prime (51613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 775 + ... + 838.

2⁵¹⁶¹⁶ is an apocalyptic number.

51616 is the 186-th centered triangular number.

It is an amenable number.

51616 is a deficient number, since it is larger than the sum of its proper divisors (50066).

51616 is a wasteful number, since it uses less digits than its factorization.

51616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1623 (or 1615 counting only the distinct ones).

The product of its digits is 180, while the sum is 19.

The square root of 51616 is about 227.1915491386. The cubic root of 51616 is about 37.2330072788.

Subtracting 51616 from its reverse (61615), we obtain a palindrome (9999).

It can be divided in two parts, 516 and 16, that multiplied together give a triangular number (8256 = T₁₂₈).

The spelling of 51616 in words is "fifty-one thousand, six hundred sixteen".