77813431 has 2 divisors, whose sum is σ = 77813432. Its totient is φ = 77813430.

The previous prime is 77813399. The next prime is 77813443. The reversal of 77813431 is 13431877.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 77813431 - 2⁵ = 77813399 is a prime.

It is a super-2 number, since 2×77813431² = 12109860087983522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77813731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38906715 + 38906716.

It is an arithmetic number, because the mean of its divisors is an integer number (38906716).

Almost surely, 2^77813431 is an apocalyptic number.

77813431 is a deficient number, since it is larger than the sum of its proper divisors (1).

77813431 is an equidigital number, since it uses as much as digits as its factorization.

77813431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14112, while the sum is 34.

The square root of 77813431 is about 8821.1921529916. The cubic root of 77813431 is about 426.9249356610.

The spelling of 77813431 in words is "seventy-seven million, eight hundred thirteen thousand, four hundred thirty-one".