21913442 has 8 divisors (see below), whose sum is σ = 34803756. Its totient is φ = 10312192.

The previous prime is 21913439. The next prime is 21913453. The reversal of 21913442 is 24431912.

It can be written as a sum of positive squares in 2 ways, for example, as 21911761 + 1681 = 4681^2 + 41^2 .

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

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, 322223 + ... + 322290.

Almost surely, 2^21913442 is an apocalyptic number.

21913442 is a deficient number, since it is larger than the sum of its proper divisors (12890314).

21913442 is a wasteful number, since it uses less digits than its factorization.

21913442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 644532.

The product of its digits is 1728, while the sum is 26.

The square root of 21913442 is about 4681.1795522069. The cubic root of 21913442 is about 279.8359668480.

The spelling of 21913442 in words is "twenty-one million, nine hundred thirteen thousand, four hundred forty-two".