81626554704 has 20 divisors (see below), whose sum is σ = 210868599776. Its totient is φ = 27208851552.

The previous prime is 81626554703. The next prime is 81626554717. The reversal of 81626554704 is 40745562618.

It is a Harshad number since it is a multiple of its sum of digits (48), and also a Moran number because the ratio is a prime number: 1700553223 = 81626554704 / (8 + 1 + 6 + 2 + 6 + 5 + 5 + 4 + 7 + 0 + 4).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81626554703) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 850276564 + ... + 850276659.

Almost surely, 2^81626554704 is an apocalyptic number.

It is an amenable number.

81626554704 is an abundant number, since it is smaller than the sum of its proper divisors (129242045072).

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

81626554704 is a wasteful number, since it uses less digits than its factorization.

81626554704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1700553234 (or 1700553228 counting only the distinct ones).

The product of its (nonzero) digits is 1612800, while the sum is 48.

The spelling of 81626554704 in words is "eighty-one billion, six hundred twenty-six million, five hundred fifty-four thousand, seven hundred four".