21862417 has 2 divisors, whose sum is σ = 21862418. Its totient is φ = 21862416.

The previous prime is 21862411. The next prime is 21862429. The reversal of 21862417 is 71426812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13242321 + 8620096 = 3639^2 + 2936^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21862417 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21862411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10931208 + 10931209.

It is an arithmetic number, because the mean of its divisors is an integer number (10931209).

Almost surely, 2^21862417 is an apocalyptic number.

It is an amenable number.

21862417 is a deficient number, since it is larger than the sum of its proper divisors (1).

21862417 is an equidigital number, since it uses as much as digits as its factorization.

21862417 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5376, while the sum is 31.

The square root of 21862417 is about 4675.7263606845. The cubic root of 21862417 is about 279.6186006142.

The spelling of 21862417 in words is "twenty-one million, eight hundred sixty-two thousand, four hundred seventeen".