81623127700 has 18 divisors (see below), whose sum is σ = 177122187326. Its totient is φ = 32649251040.

The previous prime is 81623127659. The next prime is 81623127709. The reversal of 81623127700 is 772132618.

It can be written as a sum of positive squares in 3 ways, for example, as 10400328324 + 71222799376 = 101982^2 + 266876^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 81623127700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81623127709) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 408115539 + ... + 408115738.

Almost surely, 2^81623127700 is an apocalyptic number.

It is an amenable number.

81623127700 is an abundant number, since it is smaller than the sum of its proper divisors (95499059626).

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

81623127700 is a wasteful number, since it uses less digits than its factorization.

81623127700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 816231291 (or 816231284 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 37.

The spelling of 81623127700 in words is "eighty-one billion, six hundred twenty-three million, one hundred twenty-seven thousand, seven hundred".