64020638529 has 81 divisors (see below), whose sum is σ = 102556713987. Its totient is φ = 38475689472.

The previous prime is 64020638501. The next prime is 64020638531. The reversal of 64020638529 is 92583602046.

The square root of 64020638529 is 253023.

It is a perfect power (a square), and thus also a powerful number.

64020638529 is a `hidden beast` number, since 6 + 4 + 0 + 2 + 0 + 638 + 5 + 2 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 15511457025 + 48509181504 = 124545^2 + 220248^2 .

It is not a de Polignac number, because 64020638529 - 2⁷ = 64020638401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64020638569) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 331713057 + ... + 331713249.

Almost surely, 2^64020638529 is an apocalyptic number.

64020638529 is a gapful number since it is divisible by the number (69) formed by its first and last digit.

64020638529 is the 253023-rd square number.

64020638529 is the 126512-nd centered octagonal number.

It is an amenable number.

64020638529 is a deficient number, since it is larger than the sum of its proper divisors (38536075458).

64020638529 is a wasteful number, since it uses less digits than its factorization.

64020638529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 476 (or 238 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The spelling of 64020638529 in words is "sixty-four billion, twenty million, six hundred thirty-eight thousand, five hundred twenty-nine".