81560751 has 8 divisors (see below), whose sum is σ = 109007664. Its totient is φ = 54243840.

The previous prime is 81560741. The next prime is 81560761. The reversal of 81560751 is 15706518.

It is an interprime number because it is at equal distance from previous prime (81560741) and next prime (81560761).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81560751 - 2⁵ = 81560719 is a prime.

It is a super-2 number, since 2×81560751² = 13304312207368002, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81560701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31026 + ... + 33551.

It is an arithmetic number, because the mean of its divisors is an integer number (13625958).

Almost surely, 2^81560751 is an apocalyptic number.

81560751 is a deficient number, since it is larger than the sum of its proper divisors (27446913).

81560751 is a wasteful number, since it uses less digits than its factorization.

81560751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65001.

The product of its (nonzero) digits is 8400, while the sum is 33.

The square root of 81560751 is about 9031.0991025456. The cubic root of 81560751 is about 433.6710238879.

The spelling of 81560751 in words is "eighty-one million, five hundred sixty thousand, seven hundred fifty-one".