51531530 has 8 divisors (see below), whose sum is σ = 92756772. Its totient is φ = 20612608.

The previous prime is 51531527. The next prime is 51531533. The reversal of 51531530 is 3513515.

It is an interprime number because it is at equal distance from previous prime (51531527) and next prime (51531533).

It can be written as a sum of positive squares in 2 ways, for example, as 51509329 + 22201 = 7177^2 + 149^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 51531496 and 51531505.

It is not an unprimeable number, because it can be changed into a prime (51531533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2576567 + ... + 2576586.

Almost surely, 2^51531530 is an apocalyptic number.

51531530 is a deficient number, since it is larger than the sum of its proper divisors (41225242).

51531530 is a wasteful number, since it uses less digits than its factorization.

51531530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5153160.

The product of its (nonzero) digits is 1125, while the sum is 23.

The square root of 51531530 is about 7178.5465102624. The cubic root of 51531530 is about 372.1268548366.

The spelling of 51531530 in words is "fifty-one million, five hundred thirty-one thousand, five hundred thirty".