21881627 has 2 divisors, whose sum is σ = 21881628. Its totient is φ = 21881626.

The previous prime is 21881621. The next prime is 21881647. The reversal of 21881627 is 72618812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21881627 - 2⁴ = 21881611 is a prime.

It is not a weakly prime, because it can be changed into another prime (21881621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10940813 + 10940814.

It is an arithmetic number, because the mean of its divisors is an integer number (10940814).

Almost surely, 2^21881627 is an apocalyptic number.

21881627 is a deficient number, since it is larger than the sum of its proper divisors (1).

21881627 is an equidigital number, since it uses as much as digits as its factorization.

21881627 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10752, while the sum is 35.

The square root of 21881627 is about 4677.7801359192. The cubic root of 21881627 is about 279.7004747703.

The spelling of 21881627 in words is "twenty-one million, eight hundred eighty-one thousand, six hundred twenty-seven".