64123940872 has 8 divisors (see below), whose sum is σ = 120232389150. Its totient is φ = 32061970432.

The previous prime is 64123940801. The next prime is 64123940873. The reversal of 64123940872 is 27804932146.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 35995955076 + 28127985796 = 189726^2 + 167714^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×64123940872² (a number of 22 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (64123940873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4007746297 + ... + 4007746312.

Almost surely, 2^64123940872 is an apocalyptic number.

It is an amenable number.

64123940872 is a deficient number, since it is larger than the sum of its proper divisors (56108448278).

64123940872 is a wasteful number, since it uses less digits than its factorization.

64123940872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8015492615 (or 8015492611 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 46.

The spelling of 64123940872 in words is "sixty-four billion, one hundred twenty-three million, nine hundred forty thousand, eight hundred seventy-two".