21430418 has 8 divisors (see below), whose sum is σ = 32216448. Its totient is φ = 10691604.

The previous prime is 21430403. The next prime is 21430433. The reversal of 21430418 is 81403412.

It is an interprime number because it is at equal distance from previous prime (21430403) and next prime (21430433).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 21430393 and 21430402.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10646 + ... + 12497.

It is an arithmetic number, because the mean of its divisors is an integer number (4027056).

Almost surely, 2^21430418 is an apocalyptic number.

21430418 is a deficient number, since it is larger than the sum of its proper divisors (10786030).

21430418 is a wasteful number, since it uses less digits than its factorization.

21430418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23608.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 21430418 is about 4629.2999470762. The cubic root of 21430418 is about 277.7645903191.

The spelling of 21430418 in words is "twenty-one million, four hundred thirty thousand, four hundred eighteen".