642764515 has 16 divisors (see below), whose sum is σ = 780440832. Its totient is φ = 508153824.

The previous prime is 642764513. The next prime is 642764519. The reversal of 642764515 is 515467246.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 642764515 - 2¹ = 642764513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642764513) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 259312 + ... + 261778.

It is an arithmetic number, because the mean of its divisors is an integer number (48777552).

Almost surely, 2^642764515 is an apocalyptic number.

642764515 is a deficient number, since it is larger than the sum of its proper divisors (137676317).

642764515 is a wasteful number, since it uses less digits than its factorization.

642764515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3066.

The product of its digits is 201600, while the sum is 40.

The square root of 642764515 is about 25352.8009300748. The cubic root of 642764515 is about 863.0129201438.

The spelling of 642764515 in words is "six hundred forty-two million, seven hundred sixty-four thousand, five hundred fifteen".