21174621 has 8 divisors (see below), whose sum is σ = 30404640. Its totient is φ = 13030512.

The previous prime is 21174617. The next prime is 21174631. The reversal of 21174621 is 12647112.

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

It is not a de Polignac number, because 21174621 - 2² = 21174617 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21174591 and 21174600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21174631) 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, 271431 + ... + 271508.

It is an arithmetic number, because the mean of its divisors is an integer number (3800580).

Almost surely, 2^21174621 is an apocalyptic number.

It is an amenable number.

21174621 is a deficient number, since it is larger than the sum of its proper divisors (9230019).

21174621 is a wasteful number, since it uses less digits than its factorization.

21174621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 542955.

The product of its digits is 672, while the sum is 24.

The square root of 21174621 is about 4601.5889646947. The cubic root of 21174621 is about 276.6550158801.

The spelling of 21174621 in words is "twenty-one million, one hundred seventy-four thousand, six hundred twenty-one".