81600507544 has 8 divisors (see below), whose sum is σ = 153000951660. Its totient is φ = 40800253768.

The previous prime is 81600507509. The next prime is 81600507557. The reversal of 81600507544 is 44570500618.

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 81600507497 and 81600507506.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5100031714 + ... + 5100031729.

Almost surely, 2^81600507544 is an apocalyptic number.

It is an amenable number.

81600507544 is a deficient number, since it is larger than the sum of its proper divisors (71400444116).

81600507544 is a wasteful number, since it uses less digits than its factorization.

81600507544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10200063449 (or 10200063445 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 40.

The spelling of 81600507544 in words is "eighty-one billion, six hundred million, five hundred seven thousand, five hundred forty-four".