21893653 has 4 divisors (see below), whose sum is σ = 21939840. Its totient is φ = 21847468.

The previous prime is 21893647. The next prime is 21893659. The reversal of 21893653 is 35639812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (21893647) and next prime (21893659).

It is a cyclic number.

It is not a de Polignac number, because 21893653 - 2⁵ = 21893621 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 (21893659) 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, 22375 + ... + 23332.

It is an arithmetic number, because the mean of its divisors is an integer number (5484960).

Almost surely, 2^21893653 is an apocalyptic number.

It is an amenable number.

21893653 is a deficient number, since it is larger than the sum of its proper divisors (46187).

21893653 is an equidigital number, since it uses as much as digits as its factorization.

21893653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46186.

The product of its digits is 38880, while the sum is 37.

The square root of 21893653 is about 4679.0653981324. The cubic root of 21893653 is about 279.7517059071.

The spelling of 21893653 in words is "twenty-one million, eight hundred ninety-three thousand, six hundred fifty-three".