6439910402 has 4 divisors (see below), whose sum is σ = 9659865606. Its totient is φ = 3219955200.

The previous prime is 6439910381. The next prime is 6439910419. The reversal of 6439910402 is 2040199346.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 4069291681 + 2370618721 = 63791^2 + 48689^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1609977599 + ... + 1609977602.

Almost surely, 2^6439910402 is an apocalyptic number.

6439910402 is a deficient number, since it is larger than the sum of its proper divisors (3219955204).

6439910402 is a wasteful number, since it uses less digits than its factorization.

6439910402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3219955203.

The product of its (nonzero) digits is 46656, while the sum is 38.

The square root of 6439910402 is about 80249.0523433143. The cubic root of 6439910402 is about 1860.4868654577.

The spelling of 6439910402 in words is "six billion, four hundred thirty-nine million, nine hundred ten thousand, four hundred two".