81377142400 has 192 divisors, whose sum is σ = 205201152000. Its totient is φ = 31879249920.

The previous prime is 81377142361. The next prime is 81377142401. The reversal of 81377142400 is 424177318.

It is a self number, because there is not a number n which added to its sum of digits gives 81377142400.

It is not an unprimeable number, because it can be changed into a prime (81377142401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 63624961 + ... + 63626239.

It is an arithmetic number, because the mean of its divisors is an integer number (1068756000).

Almost surely, 2^81377142400 is an apocalyptic number.

81377142400 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81377142400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102600576000).

81377142400 is an abundant number, since it is smaller than the sum of its proper divisors (123824009600).

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

81377142400 is a wasteful number, since it uses less digits than its factorization.

81377142400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1699 (or 1682 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 37.

The spelling of 81377142400 in words is "eighty-one billion, three hundred seventy-seven million, one hundred forty-two thousand, four hundred".