81588625007 has 4 divisors (see below), whose sum is σ = 83128033080. Its totient is φ = 80049216936.

The previous prime is 81588624979. The next prime is 81588625051. The reversal of 81588625007 is 70052688518.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81588625007 is a prime.

It is a super-3 number, since 3×81588625007³ (a number of 34 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81588625907) 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, 769703957 + ... + 769704062.

It is an arithmetic number, because the mean of its divisors is an integer number (20782008270).

Almost surely, 2^81588625007 is an apocalyptic number.

81588625007 is a deficient number, since it is larger than the sum of its proper divisors (1539408073).

81588625007 is a wasteful number, since it uses less digits than its factorization.

81588625007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1539408072.

The product of its (nonzero) digits is 1075200, while the sum is 50.

The spelling of 81588625007 in words is "eighty-one billion, five hundred eighty-eight million, six hundred twenty-five thousand, seven".