21998936 has 16 divisors (see below), whose sum is σ = 42670800. Its totient is φ = 10620064.

The previous prime is 21998927. The next prime is 21998947. The reversal of 21998936 is 63989912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47180 + ... + 47643.

It is an arithmetic number, because the mean of its divisors is an integer number (2666925).

Almost surely, 2^21998936 is an apocalyptic number.

It is an amenable number.

21998936 is a deficient number, since it is larger than the sum of its proper divisors (20671864).

21998936 is a wasteful number, since it uses less digits than its factorization.

21998936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94858 (or 94854 counting only the distinct ones).

The product of its digits is 209952, while the sum is 47.

The square root of 21998936 is about 4690.3023356709. The cubic root of 21998936 is about 280.1994157657.

The spelling of 21998936 in words is "twenty-one million, nine hundred ninety-eight thousand, nine hundred thirty-six".