21228654 has 16 divisors (see below), whose sum is σ = 42503760. Its totient is φ = 7068480.

The previous prime is 21228653. The next prime is 21228659. The reversal of 21228654 is 45682212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21228653) 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, 7692 + ... + 10080.

It is an arithmetic number, because the mean of its divisors is an integer number (2656485).

Almost surely, 2^21228654 is an apocalyptic number.

21228654 is an abundant number, since it is smaller than the sum of its proper divisors (21275106).

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

21228654 is a wasteful number, since it uses less digits than its factorization.

21228654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3875.

The product of its digits is 7680, while the sum is 30.

The square root of 21228654 is about 4607.4563481383. The cubic root of 21228654 is about 276.8901370245.

The spelling of 21228654 in words is "twenty-one million, two hundred twenty-eight thousand, six hundred fifty-four".