21900535 has 4 divisors (see below), whose sum is σ = 26280648. Its totient is φ = 17520424.

The previous prime is 21900533. The next prime is 21900583. The reversal of 21900535 is 53500912.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21900535 - 2¹ = 21900533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21900533) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2190049 + ... + 2190058.

It is an arithmetic number, because the mean of its divisors is an integer number (6570162).

Almost surely, 2^21900535 is an apocalyptic number.

21900535 is a deficient number, since it is larger than the sum of its proper divisors (4380113).

21900535 is an equidigital number, since it uses as much as digits as its factorization.

21900535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4380112.

The product of its (nonzero) digits is 1350, while the sum is 25.

The square root of 21900535 is about 4679.8007436215. The cubic root of 21900535 is about 279.7810150033.

The spelling of 21900535 in words is "twenty-one million, nine hundred thousand, five hundred thirty-five".