21611490 has 32 divisors (see below), whose sum is σ = 54124416. Its totient is φ = 5512320.

The previous prime is 21611461. The next prime is 21611519. The reversal of 21611490 is 9411612.

It is an interprime number because it is at equal distance from previous prime (21611461) and next prime (21611519).

It is a self number, because there is not a number n which added to its sum of digits gives 21611490.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14971 + ... + 16350.

It is an arithmetic number, because the mean of its divisors is an integer number (1691388).

Almost surely, 2^21611490 is an apocalyptic number.

21611490 is an abundant number, since it is smaller than the sum of its proper divisors (32512926).

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

21611490 is a wasteful number, since it uses less digits than its factorization.

21611490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31354.

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 21611490 is about 4648.8159782895. The cubic root of 21611490 is about 278.5447026112.

The spelling of 21611490 in words is "twenty-one million, six hundred eleven thousand, four hundred ninety".