81407502400 has 189 divisors, whose sum is σ = 233246450829. Its totient is φ = 27883752960.

The previous prime is 81407502343. The next prime is 81407502413. The reversal of 81407502400 is 420570418.

The square root of 81407502400 is 285320.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 29306700864 + 52100801536 = 171192^2 + 228256^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 79889091 + ... + 79890109.

Almost surely, 2^81407502400 is an apocalyptic number.

81407502400 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

81407502400 is the 285320-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81407502400

81407502400 is an abundant number, since it is smaller than the sum of its proper divisors (151838948429).

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

81407502400 is an equidigital number, since it uses as much as digits as its factorization.

81407502400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2074 (or 1033 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 31.

The spelling of 81407502400 in words is "eighty-one billion, four hundred seven million, five hundred two thousand, four hundred".