21908254 has 8 divisors (see below), whose sum is σ = 34592040. Its totient is φ = 10377576.

The previous prime is 21908233. The next prime is 21908261. The reversal of 21908254 is 45280912.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 288229 + ... + 288304.

It is an arithmetic number, because the mean of its divisors is an integer number (4324005).

Almost surely, 2^21908254 is an apocalyptic number.

21908254 is a deficient number, since it is larger than the sum of its proper divisors (12683786).

21908254 is a wasteful number, since it uses less digits than its factorization.

21908254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576554.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 21908254 is about 4680.6253855655. The cubic root of 21908254 is about 279.8138814147.

The spelling of 21908254 in words is "twenty-one million, nine hundred eight thousand, two hundred fifty-four".