51521553531 has 24 divisors (see below), whose sum is σ = 85110381824. Its totient is φ = 29420489520.

The previous prime is 51521553529. The next prime is 51521553533. The reversal of 51521553531 is 13535512515.

51521553531 is a `hidden beast` number, since 5 + 1 + 52 + 1 + 553 + 53 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (51521553529) and next prime (51521553533).

It is not a de Polignac number, because 51521553531 - 2¹ = 51521553529 is a prime.

It is a super-2 number, since 2×51521553531² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51521553533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 191425 + ... + 373746.

Almost surely, 2^51521553531 is an apocalyptic number.

51521553531 is a deficient number, since it is larger than the sum of its proper divisors (33588828293).

51521553531 is a wasteful number, since it uses less digits than its factorization.

51521553531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 566631 (or 566628 counting only the distinct ones).

The product of its digits is 56250, while the sum is 36.

The spelling of 51521553531 in words is "fifty-one billion, five hundred twenty-one million, five hundred fifty-three thousand, five hundred thirty-one".