51231432540 has 48 divisors (see below), whose sum is σ = 143965920672. Its totient is φ = 13612390656.

The previous prime is 51231432533. The next prime is 51231432557. The reversal of 51231432540 is 4523413215.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 51231432498 and 51231432507.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1524639 + ... + 1557878.

It is an arithmetic number, because the mean of its divisors is an integer number (2999290014).

Almost surely, 2^51231432540 is an apocalyptic number.

It is an amenable number.

51231432540 is an abundant number, since it is smaller than the sum of its proper divisors (92734488132).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51231432540 is a wasteful number, since it uses less digits than its factorization.

51231432540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3082806 (or 3082804 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 30.

Adding to 51231432540 its reverse (4523413215), we get a palindrome (55754845755).

The spelling of 51231432540 in words is "fifty-one billion, two hundred thirty-one million, four hundred thirty-two thousand, five hundred forty".