21402734 has 8 divisors (see below), whose sum is σ = 32850840. Its totient is φ = 10452456.

The previous prime is 21402713. The next prime is 21402739. The reversal of 21402734 is 43720412.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21402739) 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, 124349 + ... + 124520.

It is an arithmetic number, because the mean of its divisors is an integer number (4106355).

Almost surely, 2^21402734 is an apocalyptic number.

21402734 is a deficient number, since it is larger than the sum of its proper divisors (11448106).

21402734 is a wasteful number, since it uses less digits than its factorization.

21402734 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248914.

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 21402734 is about 4626.3088958694. The cubic root of 21402734 is about 277.6449325430.

The spelling of 21402734 in words is "twenty-one million, four hundred two thousand, seven hundred thirty-four".