21969198 has 16 divisors (see below), whose sum is σ = 48820560. Its totient is φ = 7323048.

The previous prime is 21969197. The next prime is 21969203. The reversal of 21969198 is 89196912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21969191) 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, 203365 + ... + 203472.

It is an arithmetic number, because the mean of its divisors is an integer number (3051285).

Almost surely, 2^21969198 is an apocalyptic number.

21969198 is an abundant number, since it is smaller than the sum of its proper divisors (26851362).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21969198 is a wasteful number, since it uses less digits than its factorization.

21969198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406848 (or 406842 counting only the distinct ones).

The product of its digits is 69984, while the sum is 45.

The square root of 21969198 is about 4687.1311054845. The cubic root of 21969198 is about 280.0731016614.

The spelling of 21969198 in words is "twenty-one million, nine hundred sixty-nine thousand, one hundred ninety-eight".