81560701 has 2 divisors, whose sum is σ = 81560702. Its totient is φ = 81560700.

The previous prime is 81560671. The next prime is 81560707. The reversal of 81560701 is 10706518.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61544025 + 20016676 = 7845^2 + 4474^2 .

It is a cyclic number.

It is not a de Polignac number, because 81560701 - 2⁵ = 81560669 is a prime.

It is a super-2 number, since 2×81560701² = 13304295895222802, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81560701.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81560707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40780350 + 40780351.

It is an arithmetic number, because the mean of its divisors is an integer number (40780351).

Almost surely, 2^81560701 is an apocalyptic number.

It is an amenable number.

81560701 is a deficient number, since it is larger than the sum of its proper divisors (1).

81560701 is an equidigital number, since it uses as much as digits as its factorization.

81560701 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1680, while the sum is 28.

The square root of 81560701 is about 9031.0963343328. The cubic root of 81560701 is about 433.6709352687.

It can be divided in two parts, 815 and 60701, that added together give a palindrome (61516).

The spelling of 81560701 in words is "eighty-one million, five hundred sixty thousand, seven hundred one".