21940234 has 24 divisors (see below), whose sum is σ = 35777700. Its totient is φ = 10055808.

The previous prime is 21940201. The next prime is 21940241. The reversal of 21940234 is 43204912.

It can be written as a sum of positive squares in 2 ways, for example, as 20385225 + 1555009 = 4515^2 + 1247^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21940199 and 21940208.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 62692 + ... + 63040.

Almost surely, 2^21940234 is an apocalyptic number.

21940234 is a deficient number, since it is larger than the sum of its proper divisors (13837466).

21940234 is a wasteful number, since it uses less digits than its factorization.

21940234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 454 (or 411 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 21940234 is about 4684.0403499543. The cubic root of 21940234 is about 279.9499655494.

The spelling of 21940234 in words is "twenty-one million, nine hundred forty thousand, two hundred thirty-four".