21492938 has 8 divisors (see below), whose sum is σ = 33025860. Its totient is φ = 10484320.

The previous prime is 21492937. The next prime is 21492941. The reversal of 21492938 is 83929412.

It can be written as a sum of positive squares in 2 ways, for example, as 19651489 + 1841449 = 4433^2 + 1357^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21492937) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 130973 + ... + 131136.

Almost surely, 2^21492938 is an apocalyptic number.

21492938 is a deficient number, since it is larger than the sum of its proper divisors (11532922).

21492938 is a wasteful number, since it uses less digits than its factorization.

21492938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262152.

The product of its digits is 31104, while the sum is 38.

The square root of 21492938 is about 4636.0476701604. The cubic root of 21492938 is about 278.0344401201.

The spelling of 21492938 in words is "twenty-one million, four hundred ninety-two thousand, nine hundred thirty-eight".