21046231 has 2 divisors, whose sum is σ = 21046232. Its totient is φ = 21046230.

The previous prime is 21046217. The next prime is 21046253. The reversal of 21046231 is 13264012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21046231 - 2⁹ = 21045719 is a prime.

It is a super-2 number, since 2×21046231² = 885887678610722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21046199 and 21046208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21046331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10523115 + 10523116.

It is an arithmetic number, because the mean of its divisors is an integer number (10523116).

Almost surely, 2^21046231 is an apocalyptic number.

21046231 is a deficient number, since it is larger than the sum of its proper divisors (1).

21046231 is an equidigital number, since it uses as much as digits as its factorization.

21046231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 21046231 is about 4587.6171374691. The cubic root of 21046231 is about 276.0947261144.

The spelling of 21046231 in words is "twenty-one million, forty-six thousand, two hundred thirty-one".