21740338 has 4 divisors (see below), whose sum is σ = 32610510. Its totient is φ = 10870168.

The previous prime is 21740317. The next prime is 21740347. The reversal of 21740338 is 83304712.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18688329 + 3052009 = 4323^2 + 1747^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5435083 + ... + 5435086.

Almost surely, 2^21740338 is an apocalyptic number.

21740338 is a deficient number, since it is larger than the sum of its proper divisors (10870172).

21740338 is a wasteful number, since it uses less digits than its factorization.

21740338 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10870171.

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 21740338 is about 4662.6535363460. The cubic root of 21740338 is about 279.0971685716.

The spelling of 21740338 in words is "twenty-one million, seven hundred forty thousand, three hundred thirty-eight".