21976441 has 2 divisors, whose sum is σ = 21976442. Its totient is φ = 21976440.

The previous prime is 21976439. The next prime is 21976463. The reversal of 21976441 is 14467912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15366400 + 6610041 = 3920^2 + 2571^2 .

It is a cyclic number.

It is not a de Polignac number, because 21976441 - 2¹ = 21976439 is a prime.

Together with 21976439, it forms a pair of twin primes.

It is equal to p_1387870 and since 21976441 and 1387870 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 21976397 and 21976406.

It is not a weakly prime, because it can be changed into another prime (21976421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10988220 + 10988221.

It is an arithmetic number, because the mean of its divisors is an integer number (10988221).

Almost surely, 2^21976441 is an apocalyptic number.

It is an amenable number.

21976441 is a deficient number, since it is larger than the sum of its proper divisors (1).

21976441 is an equidigital number, since it uses as much as digits as its factorization.

21976441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 34.

The square root of 21976441 is about 4687.9036892837. The cubic root of 21976441 is about 280.1038772741.

The spelling of 21976441 in words is "twenty-one million, nine hundred seventy-six thousand, four hundred forty-one".