21214988 has 6 divisors (see below), whose sum is σ = 37126236. Its totient is φ = 10607492.

The previous prime is 21214981. The next prime is 21215009. The reversal of 21214988 is 88941212.

It is not an unprimeable number, because it can be changed into a prime (21214981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2651870 + ... + 2651877.

It is an arithmetic number, because the mean of its divisors is an integer number (6187706).

Almost surely, 2^21214988 is an apocalyptic number.

It is an amenable number.

21214988 is a deficient number, since it is larger than the sum of its proper divisors (15911248).

21214988 is a wasteful number, since it uses less digits than its factorization.

21214988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5303751 (or 5303749 counting only the distinct ones).

The product of its digits is 9216, while the sum is 35.

The square root of 21214988 is about 4605.9730785145. The cubic root of 21214988 is about 276.8307080269.

The spelling of 21214988 in words is "twenty-one million, two hundred fourteen thousand, nine hundred eighty-eight".