21594031 has 2 divisors, whose sum is σ = 21594032. Its totient is φ = 21594030.

The previous prime is 21594019. The next prime is 21594047. The reversal of 21594031 is 13049512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21594031 - 2²¹ = 19496879 is a prime.

It is a super-2 number, since 2×21594031² = 932604349657922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21593987 and 21594005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21594071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10797015 + 10797016.

It is an arithmetic number, because the mean of its divisors is an integer number (10797016).

Almost surely, 2^21594031 is an apocalyptic number.

21594031 is a deficient number, since it is larger than the sum of its proper divisors (1).

21594031 is an equidigital number, since it uses as much as digits as its factorization.

21594031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 21594031 is about 4646.9378089232. The cubic root of 21594031 is about 278.4696742795.

The spelling of 21594031 in words is "twenty-one million, five hundred ninety-four thousand, thirty-one".