21470791 has 8 divisors (see below), whose sum is σ = 21775824. Its totient is φ = 21168000.

The previous prime is 21470783. The next prime is 21470807. The reversal of 21470791 is 19707412.

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

It is a cyclic number.

It is not a de Polignac number, because 21470791 - 2³ = 21470783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21470291) 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, 27985 + ... + 28741.

It is an arithmetic number, because the mean of its divisors is an integer number (2721978).

Almost surely, 2^21470791 is an apocalyptic number.

21470791 is a deficient number, since it is larger than the sum of its proper divisors (305033).

21470791 is a wasteful number, since it uses less digits than its factorization.

21470791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1121.

The product of its (nonzero) digits is 3528, while the sum is 31.

The square root of 21470791 is about 4633.6584897897. The cubic root of 21470791 is about 277.9389088195.

The spelling of 21470791 in words is "twenty-one million, four hundred seventy thousand, seven hundred ninety-one".