51620531 has 2 divisors, whose sum is σ = 51620532. Its totient is φ = 51620530.

The previous prime is 51620519. The next prime is 51620567. The reversal of 51620531 is 13502615.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51620531 - 2⁶ = 51620467 is a prime.

It is a super-2 number, since 2×51620531² = 5329358441443922, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 51620497 and 51620506.

It is not a weakly prime, because it can be changed into another prime (51620581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25810265 + 25810266.

It is an arithmetic number, because the mean of its divisors is an integer number (25810266).

Almost surely, 2^51620531 is an apocalyptic number.

51620531 is a deficient number, since it is larger than the sum of its proper divisors (1).

51620531 is an equidigital number, since it uses as much as digits as its factorization.

51620531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 900, while the sum is 23.

The square root of 51620531 is about 7184.7429320749. The cubic root of 51620531 is about 372.3409672017.

The spelling of 51620531 in words is "fifty-one million, six hundred twenty thousand, five hundred thirty-one".