6444492921 has 12 divisors (see below), whose sum is σ = 9653479472. Its totient is φ = 4296328452.

The previous prime is 6444492917. The next prime is 6444492931. The reversal of 6444492921 is 1292944446.

It is not a de Polignac number, because 6444492921 - 2² = 6444492917 is a prime.

It is a super-2 number, since 2×6444492921² = 83062978017638224482, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6444492931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13260031 + ... + 13260516.

Almost surely, 2^6444492921 is an apocalyptic number.

It is an amenable number.

6444492921 is a deficient number, since it is larger than the sum of its proper divisors (3208986551).

6444492921 is an equidigital number, since it uses as much as digits as its factorization.

6444492921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26520562 (or 26520550 counting only the distinct ones).

The product of its digits is 497664, while the sum is 45.

The square root of 6444492921 is about 80277.5991232922. The cubic root of 6444492921 is about 1860.9280566354.

The spelling of 6444492921 in words is "six billion, four hundred forty-four million, four hundred ninety-two thousand, nine hundred twenty-one".