21251193 has 8 divisors (see below), whose sum is σ = 28421856. Its totient is φ = 14124000.

The previous prime is 21251179. The next prime is 21251201. The reversal of 21251193 is 39115212.

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

It is not a de Polignac number, because 21251193 - 2⁶ = 21251129 is a prime.

It is a super-2 number, since 2×21251193² = 903226407846498, which contains 22 as substring.

It is a Curzon number.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (21251123) 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, 9708 + ... + 11693.

It is an arithmetic number, because the mean of its divisors is an integer number (3552732).

Almost surely, 2^21251193 is an apocalyptic number.

It is an amenable number.

21251193 is a deficient number, since it is larger than the sum of its proper divisors (7170663).

21251193 is a wasteful number, since it uses less digits than its factorization.

21251193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21735.

The product of its digits is 540, while the sum is 24.

The square root of 21251193 is about 4609.9016258484. The cubic root of 21251193 is about 276.9880961229.

The spelling of 21251193 in words is "twenty-one million, two hundred fifty-one thousand, one hundred ninety-three".