81588326725 has 24 divisors (see below), whose sum is σ = 102077026920. Its totient is φ = 64687576320.

The previous prime is 81588326689. The next prime is 81588326777. The reversal of 81588326725 is 52762388518.

It can be written as a sum of positive squares in 12 ways, for example, as 46297698561 + 35290628164 = 215169^2 + 187858^2 .

It is not a de Polignac number, because 81588326725 - 2¹⁹ = 81587802437 is a prime.

It is a hoax number, since the sum of its digits (55) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1341271 + ... + 1400779.

It is an arithmetic number, because the mean of its divisors is an integer number (4253209455).

Almost surely, 2^81588326725 is an apocalyptic number.

It is an amenable number.

81588326725 is a deficient number, since it is larger than the sum of its proper divisors (20488700195).

81588326725 is a wasteful number, since it uses less digits than its factorization.

81588326725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60009 (or 60004 counting only the distinct ones).

The product of its digits is 6451200, while the sum is 55.

The spelling of 81588326725 in words is "eighty-one billion, five hundred eighty-eight million, three hundred twenty-six thousand, seven hundred twenty-five".