66791737 has 2 divisors, whose sum is σ = 66791738. Its totient is φ = 66791736.

The previous prime is 66791731. The next prime is 66791749. The reversal of 66791737 is 73719766.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44475561 + 22316176 = 6669^2 + 4724^2 .

It is a cyclic number.

It is not a de Polignac number, because 66791737 - 2³ = 66791729 is a prime.

It is a super-2 number, since 2×66791737² = 8922272262954338, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66791731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33395868 + 33395869.

It is an arithmetic number, because the mean of its divisors is an integer number (33395869).

Almost surely, 2^66791737 is an apocalyptic number.

It is an amenable number.

66791737 is a deficient number, since it is larger than the sum of its proper divisors (1).

66791737 is an equidigital number, since it uses as much as digits as its factorization.

66791737 is an evil number, because the sum of its binary digits is even.

The product of its digits is 333396, while the sum is 46.

The square root of 66791737 is about 8172.6211829498. The cubic root of 66791737 is about 405.7335423113.

It can be divided in two parts, 66791 and 737, that added together give a triangular number (67528 = T₃₆₇).

The spelling of 66791737 in words is "sixty-six million, seven hundred ninety-one thousand, seven hundred thirty-seven".