21430768 has 20 divisors (see below), whose sum is σ = 42954840. Its totient is φ = 10345664.

The previous prime is 21430757. The next prime is 21430769. The reversal of 21430768 is 86703412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21430769) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22630 + ... + 23557.

It is an arithmetic number, because the mean of its divisors is an integer number (2147742).

Almost surely, 2^21430768 is an apocalyptic number.

It is an amenable number.

21430768 is an abundant number, since it is smaller than the sum of its proper divisors (21524072).

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

21430768 is a wasteful number, since it uses less digits than its factorization.

21430768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46224 (or 46218 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 21430768 is about 4629.3377496139. The cubic root of 21430768 is about 277.7661024545.

The spelling of 21430768 in words is "twenty-one million, four hundred thirty thousand, seven hundred sixty-eight".