78577231 has 2 divisors, whose sum is σ = 78577232. Its totient is φ = 78577230.

The previous prime is 78577207. The next prime is 78577237. The reversal of 78577231 is 13277587.

It is a strong prime.

It is an emirp because it is prime and its reverse (13277587) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78577231 - 2⁵ = 78577199 is a prime.

It is a super-2 number, since 2×78577231² = 12348762463254722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78577237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39288615 + 39288616.

It is an arithmetic number, because the mean of its divisors is an integer number (39288616).

Almost surely, 2^78577231 is an apocalyptic number.

78577231 is a deficient number, since it is larger than the sum of its proper divisors (1).

78577231 is an equidigital number, since it uses as much as digits as its factorization.

78577231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82320, while the sum is 40.

The square root of 78577231 is about 8864.3798993500. The cubic root of 78577231 is about 428.3172579303.

The spelling of 78577231 in words is "seventy-eight million, five hundred seventy-seven thousand, two hundred thirty-one".