21840274 has 8 divisors (see below), whose sum is σ = 34687548. Its totient is φ = 10277760.

The previous prime is 21840241. The next prime is 21840281. The reversal of 21840274 is 47204812.

It can be written as a sum of positive squares in 2 ways, for example, as 19758025 + 2082249 = 4445^2 + 1443^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 321147 + ... + 321214.

Almost surely, 2^21840274 is an apocalyptic number.

21840274 is a deficient number, since it is larger than the sum of its proper divisors (12847274).

21840274 is a wasteful number, since it uses less digits than its factorization.

21840274 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 642380.

The product of its (nonzero) digits is 3584, while the sum is 28.

The square root of 21840274 is about 4673.3578934210. The cubic root of 21840274 is about 279.5241663132.

The spelling of 21840274 in words is "twenty-one million, eight hundred forty thousand, two hundred seventy-four".