21901839 has 8 divisors (see below), whose sum is σ = 29324592. Its totient is φ = 14540160.

The previous prime is 21901837. The next prime is 21901843. The reversal of 21901839 is 93810912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21901839 - 2¹ = 21901837 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21901837) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14424 + ... + 15869.

It is an arithmetic number, because the mean of its divisors is an integer number (3665574).

Almost surely, 2^21901839 is an apocalyptic number.

21901839 is a deficient number, since it is larger than the sum of its proper divisors (7422753).

21901839 is a wasteful number, since it uses less digits than its factorization.

21901839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30537.

The product of its (nonzero) digits is 3888, while the sum is 33.

The square root of 21901839 is about 4679.9400637188. The cubic root of 21901839 is about 279.7865677931.

The spelling of 21901839 in words is "twenty-one million, nine hundred one thousand, eight hundred thirty-nine".