81968359400 has 48 divisors (see below), whose sum is σ = 201786822540. Its totient is φ = 30858675200.

The previous prime is 81968359397. The next prime is 81968359463. The reversal of 81968359400 is 495386918.

It can be written as a sum of positive squares in 6 ways, for example, as 55188346084 + 26780013316 = 234922^2 + 163646^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12050771 + ... + 12057570.

Almost surely, 2^81968359400 is an apocalyptic number.

It is an amenable number.

81968359400 is an abundant number, since it is smaller than the sum of its proper divisors (119818463140).

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

81968359400 is a wasteful number, since it uses less digits than its factorization.

81968359400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24108374 (or 24108365 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 53.

The spelling of 81968359400 in words is "eighty-one billion, nine hundred sixty-eight million, three hundred fifty-nine thousand, four hundred".