21289962 has 8 divisors (see below), whose sum is σ = 42579936. Its totient is φ = 7096652.

The previous prime is 21289949. The next prime is 21289969. The reversal of 21289962 is 26998212.

It is a sphenic number, since it is the product of 3 distinct primes.

21289962 is an admirable number.

It is a super-2 number, since 2×21289962² = 906524963922888, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21289962.

It is not an unprimeable number, because it can be changed into a prime (21289969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1774158 + ... + 1774169.

It is an arithmetic number, because the mean of its divisors is an integer number (5322492).

Almost surely, 2^21289962 is an apocalyptic number.

21289962 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21289962 is a wasteful number, since it uses less digits than its factorization.

21289962 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3548332.

The product of its digits is 31104, while the sum is 39.

The square root of 21289962 is about 4614.1046802170. The cubic root of 21289962 is about 277.1564322083.

It can be divided in two parts, 2128 and 9962, that added together give a triangular number (12090 = T₁₅₅).

The spelling of 21289962 in words is "twenty-one million, two hundred eighty-nine thousand, nine hundred sixty-two".