21998701 has 2 divisors, whose sum is σ = 21998702. Its totient is φ = 21998700.

The previous prime is 21998693. The next prime is 21998723. The reversal of 21998701 is 10789912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21996100 + 2601 = 4690^2 + 51^2 .

It is a cyclic number.

It is not a de Polignac number, because 21998701 - 2³ = 21998693 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21998761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10999350 + 10999351.

It is an arithmetic number, because the mean of its divisors is an integer number (10999351).

Almost surely, 2^21998701 is an apocalyptic number.

It is an amenable number.

21998701 is a deficient number, since it is larger than the sum of its proper divisors (1).

21998701 is an equidigital number, since it uses as much as digits as its factorization.

21998701 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 21998701 is about 4690.2772839140. The cubic root of 21998701 is about 280.1984180341.

The spelling of 21998701 in words is "twenty-one million, nine hundred ninety-eight thousand, seven hundred one".