21012254 has 16 divisors (see below), whose sum is σ = 32520096. Its totient is φ = 10176000.

The previous prime is 21012241. The next prime is 21012259. The reversal of 21012254 is 45221012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012259) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11534 + ... + 13230.

It is an arithmetic number, because the mean of its divisors is an integer number (2032506).

Almost surely, 2^21012254 is an apocalyptic number.

21012254 is a deficient number, since it is larger than the sum of its proper divisors (11507842).

21012254 is a wasteful number, since it uses less digits than its factorization.

21012254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1891.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 21012254 is about 4583.9125209803. The cubic root of 21012254 is about 275.9460704684.

Adding to 21012254 its reverse (45221012), we get a palindrome (66233266).

The spelling of 21012254 in words is "twenty-one million, twelve thousand, two hundred fifty-four".