21938154 has 16 divisors (see below), whose sum is σ = 50144448. Its totient is φ = 6268032.

The previous prime is 21938149. The next prime is 21938167. The reversal of 21938154 is 45183912.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 261127 + ... + 261210.

It is an arithmetic number, because the mean of its divisors is an integer number (3134028).

Almost surely, 2^21938154 is an apocalyptic number.

21938154 is an abundant number, since it is smaller than the sum of its proper divisors (28206294).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21938154 is a wasteful number, since it uses less digits than its factorization.

21938154 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 522349.

The product of its digits is 8640, while the sum is 33.

The square root of 21938154 is about 4683.8183141535. The cubic root of 21938154 is about 279.9411185710.

The spelling of 21938154 in words is "twenty-one million, nine hundred thirty-eight thousand, one hundred fifty-four".