21936154 has 16 divisors (see below), whose sum is σ = 34927848. Its totient is φ = 10296832.

The previous prime is 21936119. The next prime is 21936157. The reversal of 21936154 is 45163912.

It can be written as a sum of positive squares in 4 ways, for example, as 21836929 + 99225 = 4673^2 + 315^2 .

It is not an unprimeable number, because it can be changed into a prime (21936157) 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, 22542 + ... + 23494.

Almost surely, 2^21936154 is an apocalyptic number.

21936154 is a deficient number, since it is larger than the sum of its proper divisors (12991694).

21936154 is a wasteful number, since it uses less digits than its factorization.

21936154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1649.

The product of its digits is 6480, while the sum is 31.

The square root of 21936154 is about 4683.6048082647. The cubic root of 21936154 is about 279.9326113336.

The spelling of 21936154 in words is "twenty-one million, nine hundred thirty-six thousand, one hundred fifty-four".