66877913 has 2 divisors, whose sum is σ = 66877914. Its totient is φ = 66877912.

The previous prime is 66877901. The next prime is 66877919. The reversal of 66877913 is 31977866.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50580544 + 16297369 = 7112^2 + 4037^2 .

It is a cyclic number.

It is not a de Polignac number, because 66877913 - 2⁴ = 66877897 is a prime.

It is not a weakly prime, because it can be changed into another prime (66877919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33438956 + 33438957.

It is an arithmetic number, because the mean of its divisors is an integer number (33438957).

Almost surely, 2^66877913 is an apocalyptic number.

It is an amenable number.

66877913 is a deficient number, since it is larger than the sum of its proper divisors (1).

66877913 is an equidigital number, since it uses as much as digits as its factorization.

66877913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 381024, while the sum is 47.

The square root of 66877913 is about 8177.8917209755. The cubic root of 66877913 is about 405.9079624257.

Subtracting from 66877913 its sum of digits (47), we obtain a palindrome (66877866).

The spelling of 66877913 in words is "sixty-six million, eight hundred seventy-seven thousand, nine hundred thirteen".