21457274 has 12 divisors (see below), whose sum is σ = 33336654. Its totient is φ = 10357872.

The previous prime is 21457253. The next prime is 21457279. The reversal of 21457274 is 47275412.

It can be written as a sum of positive squares in 3 ways, for example, as 19228225 + 2229049 = 4385^2 + 1493^2 .

It is a super-2 number, since 2×21457274² = 920829215022152, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21457274.

It is not an unprimeable number, because it can be changed into a prime (21457279) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4697 + ... + 8060.

Almost surely, 2^21457274 is an apocalyptic number.

21457274 is a deficient number, since it is larger than the sum of its proper divisors (11879380).

21457274 is a wasteful number, since it uses less digits than its factorization.

21457274 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12817 (or 12788 counting only the distinct ones).

The product of its digits is 15680, while the sum is 32.

The square root of 21457274 is about 4632.1996934502. The cubic root of 21457274 is about 277.8805708214.

The spelling of 21457274 in words is "twenty-one million, four hundred fifty-seven thousand, two hundred seventy-four".