21246431 has 8 divisors (see below), whose sum is σ = 21906960. Its totient is φ = 20596032.

The previous prime is 21246419. The next prime is 21246443. The reversal of 21246431 is 13464212.

It is an interprime number because it is at equal distance from previous prime (21246419) and next prime (21246443).

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 21246431 - 2⁶ = 21246367 is a prime.

It is a super-2 number, since 2×21246431² = 902821660475522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21246397 and 21246406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21246131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1841 + ... + 6773.

It is an arithmetic number, because the mean of its divisors is an integer number (2738370).

Almost surely, 2^21246431 is an apocalyptic number.

21246431 is a deficient number, since it is larger than the sum of its proper divisors (660529).

21246431 is an equidigital number, since it uses as much as digits as its factorization.

21246431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5065.

The product of its digits is 1152, while the sum is 23.

The square root of 21246431 is about 4609.3850999889. The cubic root of 21246431 is about 276.9674052712.

The spelling of 21246431 in words is "twenty-one million, two hundred forty-six thousand, four hundred thirty-one".