21907230 has 32 divisors (see below), whose sum is σ = 52700544. Its totient is φ = 5828256.

The previous prime is 21907229. The next prime is 21907279. The reversal of 21907230 is 3270912.

It is a self number, because there is not a number n which added to its sum of digits gives 21907230.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24369 + ... + 25251.

It is an arithmetic number, because the mean of its divisors is an integer number (1646892).

Almost surely, 2^21907230 is an apocalyptic number.

21907230 is an abundant number, since it is smaller than the sum of its proper divisors (30793314).

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

21907230 is a wasteful number, since it uses less digits than its factorization.

21907230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1720.

The product of its (nonzero) digits is 756, while the sum is 24.

The square root of 21907230 is about 4680.5159971952. The cubic root of 21907230 is about 279.8095218116.

The spelling of 21907230 in words is "twenty-one million, nine hundred seven thousand, two hundred thirty".