21103254 has 20 divisors (see below), whose sum is σ = 47287284. Its totient is φ = 7034364.

The previous prime is 21103253. The next prime is 21103267. The reversal of 21103254 is 45230112.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21103253) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 64972 + ... + 65295.

Almost surely, 2^21103254 is an apocalyptic number.

21103254 is an abundant number, since it is smaller than the sum of its proper divisors (26184030).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21103254 is a wasteful number, since it uses less digits than its factorization.

21103254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130281 (or 130272 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 21103254 is about 4593.8278156675. The cubic root of 21103254 is about 276.3438530981.

Adding to 21103254 its reverse (45230112), we get a palindrome (66333366).

The spelling of 21103254 in words is "twenty-one million, one hundred three thousand, two hundred fifty-four".