6990189921 has 40 divisors (see below), whose sum is σ = 12267704064. Its totient is φ = 3910589280.

The previous prime is 6990189919. The next prime is 6990189949. The reversal of 6990189921 is 1299810996.

It is not a de Polignac number, because 6990189921 - 2¹ = 6990189919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6990189911) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 290161 + ... + 313326.

Almost surely, 2^6990189921 is an apocalyptic number.

It is an amenable number.

6990189921 is a deficient number, since it is larger than the sum of its proper divisors (5277514143).

6990189921 is a wasteful number, since it uses less digits than its factorization.

6990189921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 603523 (or 603514 counting only the distinct ones).

The product of its (nonzero) digits is 629856, while the sum is 54.

The square root of 6990189921 is about 83607.3556632429. The cubic root of 6990189921 is about 1912.0371456613.

The spelling of 6990189921 in words is "six billion, nine hundred ninety million, one hundred eighty-nine thousand, nine hundred twenty-one".