77725231 has 2 divisors, whose sum is σ = 77725232. Its totient is φ = 77725230.

The previous prime is 77725223. The next prime is 77725261. The reversal of 77725231 is 13252777.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (13252777) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77725231 - 2³ = 77725223 is a prime.

It is a super-2 number, since 2×77725231² = 12082423068006722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77725261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38862615 + 38862616.

It is an arithmetic number, because the mean of its divisors is an integer number (38862616).

Almost surely, 2^77725231 is an apocalyptic number.

77725231 is a deficient number, since it is larger than the sum of its proper divisors (1).

77725231 is an equidigital number, since it uses as much as digits as its factorization.

77725231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20580, while the sum is 34.

The square root of 77725231 is about 8816.1914112614. The cubic root of 77725231 is about 426.7635709935.

The spelling of 77725231 in words is "seventy-seven million, seven hundred twenty-five thousand, two hundred thirty-one".