77121331 has 16 divisors (see below), whose sum is σ = 89362944. Its totient is φ = 65193984.

The previous prime is 77121311. The next prime is 77121337. The reversal of 77121331 is 13312177.

It is a cyclic number.

It is not a de Polignac number, because 77121331 - 2⁷ = 77121203 is a prime.

It is a super-2 number, since 2×77121331² = 11895399390423122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77121296 and 77121305.

It is not an unprimeable number, because it can be changed into a prime (77121337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 293106 + ... + 293368.

It is an arithmetic number, because the mean of its divisors is an integer number (5585184).

Almost surely, 2^77121331 is an apocalyptic number.

77121331 is a deficient number, since it is larger than the sum of its proper divisors (12241613).

77121331 is a wasteful number, since it uses less digits than its factorization.

77121331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 690.

The product of its digits is 882, while the sum is 25.

The square root of 77121331 is about 8781.8751414490. The cubic root of 77121331 is about 425.6554242266.

The spelling of 77121331 in words is "seventy-seven million, one hundred twenty-one thousand, three hundred thirty-one".