21846961 has 2 divisors, whose sum is σ = 21846962. Its totient is φ = 21846960.

The previous prime is 21846949. The next prime is 21846991. The reversal of 21846961 is 16964812.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20647936 + 1199025 = 4544^2 + 1095^2 .

It is a cyclic number.

It is not a de Polignac number, because 21846961 - 2⁷ = 21846833 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21846961.

It is not a weakly prime, because it can be changed into another prime (21846901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10923480 + 10923481.

It is an arithmetic number, because the mean of its divisors is an integer number (10923481).

Almost surely, 2^21846961 is an apocalyptic number.

It is an amenable number.

21846961 is a deficient number, since it is larger than the sum of its proper divisors (1).

21846961 is an equidigital number, since it uses as much as digits as its factorization.

21846961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 37.

The square root of 21846961 is about 4674.0732771321. The cubic root of 21846961 is about 279.5526914036.

The spelling of 21846961 in words is "twenty-one million, eight hundred forty-six thousand, nine hundred sixty-one".