81637036061 has 16 divisors (see below), whose sum is σ = 98870768640. Its totient is φ = 65913832320.

The previous prime is 81637036051. The next prime is 81637036069. The reversal of 81637036061 is 16063073618.

It is not a de Polignac number, because 81637036061 - 2¹⁴ = 81637019677 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81637036069) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4895981 + ... + 4912626.

It is an arithmetic number, because the mean of its divisors is an integer number (6179423040).

Almost surely, 2^81637036061 is an apocalyptic number.

It is an amenable number.

81637036061 is a deficient number, since it is larger than the sum of its proper divisors (17233732579).

81637036061 is a wasteful number, since it uses less digits than its factorization.

81637036061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9808684.

The product of its (nonzero) digits is 108864, while the sum is 41.

The spelling of 81637036061 in words is "eighty-one billion, six hundred thirty-seven million, thirty-six thousand, sixty-one".