64661197 has 2 divisors, whose sum is σ = 64661198. Its totient is φ = 64661196.

The previous prime is 64661173. The next prime is 64661203. The reversal of 64661197 is 79116646.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42954916 + 21706281 = 6554^2 + 4659^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64661197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64661117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32330598 + 32330599.

It is an arithmetic number, because the mean of its divisors is an integer number (32330599).

Almost surely, 2^64661197 is an apocalyptic number.

It is an amenable number.

64661197 is a deficient number, since it is larger than the sum of its proper divisors (1).

64661197 is an equidigital number, since it uses as much as digits as its factorization.

64661197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 40.

The square root of 64661197 is about 8041.2186265516. The cubic root of 64661197 is about 401.3727770682.

The spelling of 64661197 in words is "sixty-four million, six hundred sixty-one thousand, one hundred ninety-seven".