21652090 has 16 divisors (see below), whose sum is σ = 39710088. Its totient is φ = 8497216.

The previous prime is 21652063. The next prime is 21652121. The reversal of 21652090 is 9025612.

It can be written as a sum of positive squares in 4 ways, for example, as 21650409 + 1681 = 4653^2 + 41^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19897 + ... + 20956.

Almost surely, 2^21652090 is an apocalyptic number.

21652090 is a deficient number, since it is larger than the sum of its proper divisors (18057998).

21652090 is a wasteful number, since it uses less digits than its factorization.

21652090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40913.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 21652090 is about 4653.1806326426. The cubic root of 21652090 is about 278.7190210031.

The spelling of 21652090 in words is "twenty-one million, six hundred fifty-two thousand, ninety".