77949251 has 2 divisors, whose sum is σ = 77949252. Its totient is φ = 77949250.

The previous prime is 77949247. The next prime is 77949259. The reversal of 77949251 is 15294977.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 77949251 - 2² = 77949247 is a prime.

It is a super-2 number, since 2×77949251² = 12152171462922002, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77949259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38974625 + 38974626.

It is an arithmetic number, because the mean of its divisors is an integer number (38974626).

Almost surely, 2^77949251 is an apocalyptic number.

77949251 is a deficient number, since it is larger than the sum of its proper divisors (1).

77949251 is an equidigital number, since it uses as much as digits as its factorization.

77949251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 158760, while the sum is 44.

The square root of 77949251 is about 8828.8873024861. The cubic root of 77949251 is about 427.1731843243.

The spelling of 77949251 in words is "seventy-seven million, nine hundred forty-nine thousand, two hundred fifty-one".