21983671 has 2 divisors, whose sum is σ = 21983672. Its totient is φ = 21983670.

The previous prime is 21983641. The next prime is 21983683. The reversal of 21983671 is 17638912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21983671 - 2²³ = 13595063 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21983671.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21983641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10991835 + 10991836.

It is an arithmetic number, because the mean of its divisors is an integer number (10991836).

Almost surely, 2^21983671 is an apocalyptic number.

21983671 is a deficient number, since it is larger than the sum of its proper divisors (1).

21983671 is an equidigital number, since it uses as much as digits as its factorization.

21983671 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 37.

The square root of 21983671 is about 4688.6747594603. The cubic root of 21983671 is about 280.1345909065.

The spelling of 21983671 in words is "twenty-one million, nine hundred eighty-three thousand, six hundred seventy-one".