51531612372 has 96 divisors (see below), whose sum is σ = 142492573440. Its totient is φ = 16048696320.

The previous prime is 51531612331. The next prime is 51531612383. The reversal of 51531612372 is 27321613515.

51531612372 is a `hidden beast` number, since 5 + 1 + 5 + 3 + 1 + 612 + 37 + 2 = 666.

51531612372 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 149097 + ... + 353967.

It is an arithmetic number, because the mean of its divisors is an integer number (1484297640).

Almost surely, 2^51531612372 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51531612372, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71246286720).

51531612372 is an abundant number, since it is smaller than the sum of its proper divisors (90960961068).

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

51531612372 is a wasteful number, since it uses less digits than its factorization.

51531612372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205038 (or 205030 counting only the distinct ones).

The product of its digits is 37800, while the sum is 36.

The spelling of 51531612372 in words is "fifty-one billion, five hundred thirty-one million, six hundred twelve thousand, three hundred seventy-two".