64491899 has 2 divisors, whose sum is σ = 64491900. Its totient is φ = 64491898.

The previous prime is 64491883. The next prime is 64491901. The reversal of 64491899 is 99819446.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 64491899 - 2⁴ = 64491883 is a prime.

Together with 64491901, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (64491599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32245949 + 32245950.

It is an arithmetic number, because the mean of its divisors is an integer number (32245950).

Almost surely, 2^64491899 is an apocalyptic number.

64491899 is a deficient number, since it is larger than the sum of its proper divisors (1).

64491899 is an equidigital number, since it uses as much as digits as its factorization.

64491899 is an evil number, because the sum of its binary digits is even.

The product of its digits is 559872, while the sum is 50.

The square root of 64491899 is about 8030.6848400370. The cubic root of 64491899 is about 401.0221752527.

The spelling of 64491899 in words is "sixty-four million, four hundred ninety-one thousand, eight hundred ninety-nine".