76721161 has 4 divisors (see below), whose sum is σ = 83695824. Its totient is φ = 69746500.

The previous prime is 76721147. The next prime is 76721173. The reversal of 76721161 is 16112767.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 76721161 - 2⁵ = 76721129 is a prime.

It is a super-2 number, since 2×76721161² = 11772273090375842, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (76721101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3487315 + ... + 3487336.

It is an arithmetic number, because the mean of its divisors is an integer number (20923956).

Almost surely, 2^76721161 is an apocalyptic number.

It is an amenable number.

76721161 is a deficient number, since it is larger than the sum of its proper divisors (6974663).

76721161 is a wasteful number, since it uses less digits than its factorization.

76721161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6974662.

The product of its digits is 3528, while the sum is 31.

The square root of 76721161 is about 8759.0616506564. The cubic root of 76721161 is about 424.9179283275.

The spelling of 76721161 in words is "seventy-six million, seven hundred twenty-one thousand, one hundred sixty-one".