21901427 has 2 divisors, whose sum is σ = 21901428. Its totient is φ = 21901426.

The previous prime is 21901403. The next prime is 21901463. The reversal of 21901427 is 72410912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21901427 - 2⁸ = 21901171 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21901396 and 21901405.

It is not a weakly prime, because it can be changed into another prime (21900427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10950713 + 10950714.

It is an arithmetic number, because the mean of its divisors is an integer number (10950714).

Almost surely, 2^21901427 is an apocalyptic number.

21901427 is a deficient number, since it is larger than the sum of its proper divisors (1).

21901427 is an equidigital number, since it uses as much as digits as its factorization.

21901427 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 21901427 is about 4679.8960458540. The cubic root of 21901427 is about 279.7848134079.

The spelling of 21901427 in words is "twenty-one million, nine hundred one thousand, four hundred twenty-seven".