6643742451 has 8 divisors (see below), whose sum is σ = 8866402704. Its totient is φ = 4425121920.

The previous prime is 6643742449. The next prime is 6643742503. The reversal of 6643742451 is 1542473466.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6643742451 - 2¹ = 6643742449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6643742431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1006090 + ... + 1012671.

It is an arithmetic number, because the mean of its divisors is an integer number (1108300338).

Almost surely, 2^6643742451 is an apocalyptic number.

6643742451 is a deficient number, since it is larger than the sum of its proper divisors (2222660253).

6643742451 is a wasteful number, since it uses less digits than its factorization.

6643742451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2019861.

The product of its digits is 483840, while the sum is 42.

The square root of 6643742451 is about 81509.1556268374. The cubic root of 6643742451 is about 1879.9123290752.

The spelling of 6643742451 in words is "six billion, six hundred forty-three million, seven hundred forty-two thousand, four hundred fifty-one".