643456515 has 48 divisors (see below), whose sum is σ = 1140936192. Its totient is φ = 309359232.

The previous prime is 643456481. The next prime is 643456547. The reversal of 643456515 is 515654346.

It is not a de Polignac number, because 643456515 - 2⁹ = 643456003 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 106054 + ... + 111956.

It is an arithmetic number, because the mean of its divisors is an integer number (23769504).

Almost surely, 2^643456515 is an apocalyptic number.

643456515 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

643456515 is a deficient number, since it is larger than the sum of its proper divisors (497479677).

643456515 is a wasteful number, since it uses less digits than its factorization.

643456515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5980 (or 5967 counting only the distinct ones).

The product of its digits is 216000, while the sum is 39.

The square root of 643456515 is about 25366.4446661332. Note that the first 3 decimals coincide. The cubic root of 643456515 is about 863.3225155130.

The spelling of 643456515 in words is "six hundred forty-three million, four hundred fifty-six thousand, five hundred fifteen".