77312947 has 2 divisors, whose sum is σ = 77312948. Its totient is φ = 77312946.

The previous prime is 77312929. The next prime is 77312969. The reversal of 77312947 is 74921377.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 77312947 - 2¹⁹ = 76788659 is a prime.

It is not a weakly prime, because it can be changed into another prime (77312987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38656473 + 38656474.

It is an arithmetic number, because the mean of its divisors is an integer number (38656474).

Almost surely, 2^77312947 is an apocalyptic number.

77312947 is a deficient number, since it is larger than the sum of its proper divisors (1).

77312947 is an equidigital number, since it uses as much as digits as its factorization.

77312947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 74088, while the sum is 40.

The square root of 77312947 is about 8792.7781161587. The cubic root of 77312947 is about 426.0076611140.

The spelling of 77312947 in words is "seventy-seven million, three hundred twelve thousand, nine hundred forty-seven".