21402246 has 48 divisors (see below), whose sum is σ = 46469808. Its totient is φ = 6566400.

The previous prime is 21402239. The next prime is 21402253. The reversal of 21402246 is 64220412.

It is an interprime number because it is at equal distance from previous prime (21402239) and next prime (21402253).

It is a super-2 number, since 2×21402246² = 916112267689032, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 88686 + ... + 88926.

It is an arithmetic number, because the mean of its divisors is an integer number (968121).

Almost surely, 2^21402246 is an apocalyptic number.

21402246 is an abundant number, since it is smaller than the sum of its proper divisors (25067562).

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

21402246 is a wasteful number, since it uses less digits than its factorization.

21402246 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 325 (or 306 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 21402246 is about 4626.2561537381. The cubic root of 21402246 is about 277.6428223491.

Adding to 21402246 its reverse (64220412), we get a palindrome (85622658).

The spelling of 21402246 in words is "twenty-one million, four hundred two thousand, two hundred forty-six".