99664261 has 2 divisors, whose sum is σ = 99664262. Its totient is φ = 99664260.

The previous prime is 99664249. The next prime is 99664277. The reversal of 99664261 is 16246699.

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., 93508900 + 6155361 = 9670^2 + 2481^2 .

It is a cyclic number.

It is not a de Polignac number, because 99664261 - 2¹⁹ = 99139973 is a prime.

It is a super-2 number, since 2×99664261² = 19865929841352242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99664241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49832130 + 49832131.

It is an arithmetic number, because the mean of its divisors is an integer number (49832131).

Almost surely, 2^99664261 is an apocalyptic number.

It is an amenable number.

99664261 is a deficient number, since it is larger than the sum of its proper divisors (1).

99664261 is an equidigital number, since it uses as much as digits as its factorization.

99664261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 43.

The square root of 99664261 is about 9983.1989362128. The cubic root of 99664261 is about 463.6388468067.

The spelling of 99664261 in words is "ninety-nine million, six hundred sixty-four thousand, two hundred sixty-one".