21250099 has 8 divisors (see below), whose sum is σ = 23503760. Its totient is φ = 19084896.

The previous prime is 21250067. The next prime is 21250111. The reversal of 21250099 is 99005212.

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

It is not a de Polignac number, because 21250099 - 2⁵ = 21250067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21250039) 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, 21609 + ... + 22570.

It is an arithmetic number, because the mean of its divisors is an integer number (2937970).

Almost surely, 2^21250099 is an apocalyptic number.

21250099 is a deficient number, since it is larger than the sum of its proper divisors (2253661).

21250099 is a wasteful number, since it uses less digits than its factorization.

21250099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44229.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 21250099 is about 4609.7829666916. The cubic root of 21250099 is about 276.9833429752.

The spelling of 21250099 in words is "twenty-one million, two hundred fifty thousand, ninety-nine".