21352988 has 12 divisors (see below), whose sum is σ = 37466520. Its totient is φ = 10648272.

The previous prime is 21352987. The next prime is 21352997. The reversal of 21352988 is 88925312.

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21352987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5306 + ... + 8417.

It is an arithmetic number, because the mean of its divisors is an integer number (3122210).

Almost surely, 2^21352988 is an apocalyptic number.

It is an amenable number.

21352988 is a deficient number, since it is larger than the sum of its proper divisors (16113532).

21352988 is a wasteful number, since it uses less digits than its factorization.

21352988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14116 (or 14114 counting only the distinct ones).

The product of its digits is 34560, while the sum is 38.

The square root of 21352988 is about 4620.9293437576. The cubic root of 21352988 is about 277.4296572510.

The spelling of 21352988 in words is "twenty-one million, three hundred fifty-two thousand, nine hundred eighty-eight".