51461531 has 4 divisors (see below), whose sum is σ = 56139864. Its totient is φ = 46783200.

The previous prime is 51461513. The next prime is 51461537. The reversal of 51461531 is 13516415.

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-51461531 is a prime.

It is a super-2 number, since 2×51461531² = 5296578345727922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51461531.

It is not an unprimeable number, because it can be changed into a prime (51461537) 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, 2339150 + ... + 2339171.

It is an arithmetic number, because the mean of its divisors is an integer number (14034966).

Almost surely, 2^51461531 is an apocalyptic number.

51461531 is a deficient number, since it is larger than the sum of its proper divisors (4678333).

51461531 is a wasteful number, since it uses less digits than its factorization.

51461531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4678332.

The product of its digits is 1800, while the sum is 26.

The square root of 51461531 is about 7173.6692842645. The cubic root of 51461531 is about 371.9582828889.

Adding to 51461531 its reverse (13516415), we get a palindrome (64977946).

Subtracting from 51461531 its reverse (13516415), we obtain a triangular number (37945116 = T₈₇₁₁).

The spelling of 51461531 in words is "fifty-one million, four hundred sixty-one thousand, five hundred thirty-one".