21423734 has 8 divisors (see below), whose sum is σ = 32252448. Its totient is φ = 10672920.

The previous prime is 21423709. The next prime is 21423751. The reversal of 21423734 is 43732412.

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

It is a congruent number.

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, 18782 + ... + 19889.

It is an arithmetic number, because the mean of its divisors is an integer number (4031556).

Almost surely, 2^21423734 is an apocalyptic number.

21423734 is a deficient number, since it is larger than the sum of its proper divisors (10828714).

21423734 is a wasteful number, since it uses less digits than its factorization.

21423734 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38950.

The product of its digits is 4032, while the sum is 26.

The square root of 21423734 is about 4628.5779673675. The cubic root of 21423734 is about 277.7357096945.

The spelling of 21423734 in words is "twenty-one million, four hundred twenty-three thousand, seven hundred thirty-four".