64400752499 has 4 divisors (see below), whose sum is σ = 66478196160. Its totient is φ = 62323308840.

The previous prime is 64400752489. The next prime is 64400752511. The reversal of 64400752499 is 99425700446.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 64400752499 - 2¹⁶ = 64400686963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64400752489) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1038721784 + ... + 1038721845.

It is an arithmetic number, because the mean of its divisors is an integer number (16619549040).

Almost surely, 2^64400752499 is an apocalyptic number.

64400752499 is a deficient number, since it is larger than the sum of its proper divisors (2077443661).

64400752499 is a wasteful number, since it uses less digits than its factorization.

64400752499 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2077443660.

The product of its (nonzero) digits is 2177280, while the sum is 50.

The spelling of 64400752499 in words is "sixty-four billion, four hundred million, seven hundred fifty-two thousand, four hundred ninety-nine".