21612827 has 2 divisors, whose sum is σ = 21612828. Its totient is φ = 21612826.

The previous prime is 21612769. The next prime is 21612839. The reversal of 21612827 is 72821612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21612827 - 2¹⁰ = 21611803 is a prime.

It is a super-2 number, since 2×21612827² = 934228581863858, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21612827.

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, 10806413 + 10806414.

It is an arithmetic number, because the mean of its divisors is an integer number (10806414).

Almost surely, 2^21612827 is an apocalyptic number.

21612827 is a deficient number, since it is larger than the sum of its proper divisors (1).

21612827 is an equidigital number, since it uses as much as digits as its factorization.

21612827 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2688, while the sum is 29.

The square root of 21612827 is about 4648.9597761220. The cubic root of 21612827 is about 278.5504465710.

The spelling of 21612827 in words is "twenty-one million, six hundred twelve thousand, eight hundred twenty-seven".