77991253 has 2 divisors, whose sum is σ = 77991254. Its totient is φ = 77991252.

The previous prime is 77991241. The next prime is 77991313. The reversal of 77991253 is 35219977.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77845329 + 145924 = 8823^2 + 382^2 .

It is a cyclic number.

It is not a de Polignac number, because 77991253 - 2⁹ = 77990741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77991233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38995626 + 38995627.

It is an arithmetic number, because the mean of its divisors is an integer number (38995627).

Almost surely, 2^77991253 is an apocalyptic number.

It is an amenable number.

77991253 is a deficient number, since it is larger than the sum of its proper divisors (1).

77991253 is an equidigital number, since it uses as much as digits as its factorization.

77991253 is an evil number, because the sum of its binary digits is even.

The product of its digits is 119070, while the sum is 43.

The square root of 77991253 is about 8831.2656510831. The cubic root of 77991253 is about 427.2498962285.

The spelling of 77991253 in words is "seventy-seven million, nine hundred ninety-one thousand, two hundred fifty-three".