21246251 has 8 divisors (see below), whose sum is σ = 23499504. Its totient is φ = 19081440.

The previous prime is 21246229. The next prime is 21246263. The reversal of 21246251 is 15264212.

It is a happy number.

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 21246251 - 2⁶ = 21246187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21246221) 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, 21605 + ... + 22566.

It is an arithmetic number, because the mean of its divisors is an integer number (2937438).

Almost surely, 2^21246251 is an apocalyptic number.

21246251 is a deficient number, since it is larger than the sum of its proper divisors (2253253).

21246251 is a wasteful number, since it uses less digits than its factorization.

21246251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44221.

The product of its digits is 960, while the sum is 23.

The square root of 21246251 is about 4609.3655745666. The cubic root of 21246251 is about 276.9666231120.

The spelling of 21246251 in words is "twenty-one million, two hundred forty-six thousand, two hundred fifty-one".