6439961938442 has 4 divisors (see below), whose sum is σ = 9659942907666. Its totient is φ = 3219980969220.

The previous prime is 6439961938411. The next prime is 6439961938451. The reversal of 6439961938442 is 2448391699346.

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., 4940613117001 + 1499348821441 = 2222749^2 + 1224479^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1609990484609 + ... + 1609990484612.

Almost surely, 2^{6439961938442} is an apocalyptic number.

6439961938442 is a deficient number, since it is larger than the sum of its proper divisors (3219980969224).

6439961938442 is a wasteful number, since it uses less digits than its factorization.

6439961938442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3219980969223.

The product of its digits is 241864704, while the sum is 68.

The spelling of 6439961938442 in words is "six trillion, four hundred thirty-nine billion, nine hundred sixty-one million, nine hundred thirty-eight thousand, four hundred forty-two".