81037669057 has 2 divisors, whose sum is σ = 81037669058. Its totient is φ = 81037669056.

The previous prime is 81037669021. The next prime is 81037669081. The reversal of 81037669057 is 75096673018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49339071376 + 31698597681 = 222124^2 + 178041^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81037669057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81037668995 and 81037669013.

It is not a weakly prime, because it can be changed into another prime (81037669457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40518834528 + 40518834529.

It is an arithmetic number, because the mean of its divisors is an integer number (40518834529).

Almost surely, 2^81037669057 is an apocalyptic number.

It is an amenable number.

81037669057 is a deficient number, since it is larger than the sum of its proper divisors (1).

81037669057 is an equidigital number, since it uses as much as digits as its factorization.

81037669057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1905120, while the sum is 52.

The spelling of 81037669057 in words is "eighty-one billion, thirty-seven million, six hundred sixty-nine thousand, fifty-seven".