21939254 has 16 divisors (see below), whose sum is σ = 34186320. Its totient is φ = 10547040.

The previous prime is 21939241. The next prime is 21939277. The reversal of 21939254 is 45293912.

It is a congruent number.

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, 16349 + ... + 17639.

It is an arithmetic number, because the mean of its divisors is an integer number (2136645).

Almost surely, 2^21939254 is an apocalyptic number.

21939254 is a deficient number, since it is larger than the sum of its proper divisors (12247066).

21939254 is a wasteful number, since it uses less digits than its factorization.

21939254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1615.

The product of its digits is 19440, while the sum is 35.

The square root of 21939254 is about 4683.9357382441. The cubic root of 21939254 is about 279.9457973312.

The spelling of 21939254 in words is "twenty-one million, nine hundred thirty-nine thousand, two hundred fifty-four".