6648692021 has 4 divisors (see below), whose sum is σ = 6998623200. Its totient is φ = 6298760844.

The previous prime is 6648691943. The next prime is 6648692033. The reversal of 6648692021 is 1202968466.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6648692021 - 2¹⁸ = 6648429877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6648692821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 174965561 + ... + 174965598.

It is an arithmetic number, because the mean of its divisors is an integer number (1749655800).

Almost surely, 2^6648692021 is an apocalyptic number.

It is an amenable number.

6648692021 is a deficient number, since it is larger than the sum of its proper divisors (349931179).

6648692021 is a wasteful number, since it uses less digits than its factorization.

6648692021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 349931178.

The product of its (nonzero) digits is 248832, while the sum is 44.

The square root of 6648692021 is about 81539.5120233130. The cubic root of 6648692021 is about 1880.3790563763.

The spelling of 6648692021 in words is "six billion, six hundred forty-eight million, six hundred ninety-two thousand, twenty-one".