81372398580 has 192 divisors, whose sum is σ = 290708812800. Its totient is φ = 18688371840.

The previous prime is 81372398551. The next prime is 81372398581. The reversal of 81372398580 is 8589327318.

81372398580 is a `hidden beast` number, since 8 + 1 + 37 + 23 + 9 + 8 + 580 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81372398581) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 247642 + ... + 473361.

It is an arithmetic number, because the mean of its divisors is an integer number (1514108400).

Almost surely, 2^81372398580 is an apocalyptic number.

It is an amenable number.

81372398580 is an abundant number, since it is smaller than the sum of its proper divisors (209336414220).

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

81372398580 is a wasteful number, since it uses less digits than its factorization.

81372398580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 721051 (or 721043 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The spelling of 81372398580 in words is "eighty-one billion, three hundred seventy-two million, three hundred ninety-eight thousand, five hundred eighty".