21612883 has 2 divisors, whose sum is σ = 21612884. Its totient is φ = 21612882.

The previous prime is 21612869. The next prime is 21612887. The reversal of 21612883 is 38821612.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21612883 is a prime.

It is not a weakly prime, because it can be changed into another prime (21612887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10806441 + 10806442.

It is an arithmetic number, because the mean of its divisors is an integer number (10806442).

Almost surely, 2^21612883 is an apocalyptic number.

21612883 is a deficient number, since it is larger than the sum of its proper divisors (1).

21612883 is an equidigital number, since it uses as much as digits as its factorization.

21612883 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 31.

The square root of 21612883 is about 4648.9657989708. The cubic root of 21612883 is about 278.5506871505.

The spelling of 21612883 in words is "twenty-one million, six hundred twelve thousand, eight hundred eighty-three".