615138864 has 80 divisors (see below), whose sum is σ = 1667369472. Its totient is φ = 195047424.

The previous prime is 615138847. The next prime is 615138883. The reversal of 615138864 is 468831516.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 211629 + ... + 214515.

Almost surely, 2^615138864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 615138864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (833684736).

615138864 is an abundant number, since it is smaller than the sum of its proper divisors (1052230608).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

615138864 is a wasteful number, since it uses less digits than its factorization.

615138864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3114 (or 3108 counting only the distinct ones).

The product of its digits is 138240, while the sum is 42.

The square root of 615138864 is about 24801.9931457131. The cubic root of 615138864 is about 850.4675001518.

The spelling of 615138864 in words is "six hundred fifteen million, one hundred thirty-eight thousand, eight hundred sixty-four".