79815887 has 2 divisors, whose sum is σ = 79815888. Its totient is φ = 79815886.

The previous prime is 79815881. The next prime is 79815893. The reversal of 79815887 is 78851897.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (79815881) and next prime (79815893).

It is a cyclic number.

It is not a de Polignac number, because 79815887 - 2¹² = 79811791 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79815881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39907943 + 39907944.

It is an arithmetic number, because the mean of its divisors is an integer number (39907944).

Almost surely, 2^79815887 is an apocalyptic number.

79815887 is a deficient number, since it is larger than the sum of its proper divisors (1).

79815887 is an equidigital number, since it uses as much as digits as its factorization.

79815887 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1128960, while the sum is 53.

The square root of 79815887 is about 8933.9737519203. The cubic root of 79815887 is about 430.5561345763.

The spelling of 79815887 in words is "seventy-nine million, eight hundred fifteen thousand, eight hundred eighty-seven".