55431537840 has 640 divisors, whose sum is σ = 231342336000. Its totient is φ = 11917062144.

The previous prime is 55431537839. The next prime is 55431537851. The reversal of 55431537840 is 4873513455.

It is a happy number.

55431537840 is a `hidden beast` number, since 5 + 5 + 4 + 31 + 537 + 84 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 45102346 + ... + 45103574.

It is an arithmetic number, because the mean of its divisors is an integer number (361472400).

Almost surely, 2^55431537840 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 55431537840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115671168000).

55431537840 is an abundant number, since it is smaller than the sum of its proper divisors (175910798160).

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

55431537840 is a wasteful number, since it uses less digits than its factorization.

55431537840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1434 (or 1422 counting only the distinct ones).

The product of its (nonzero) digits is 1008000, while the sum is 45.

The spelling of 55431537840 in words is "fifty-five billion, four hundred thirty-one million, five hundred thirty-seven thousand, eight hundred forty".