21862685197 has 4 divisors (see below), whose sum is σ = 21865139356. Its totient is φ = 21860231040.

The previous prime is 21862685191. The next prime is 21862685203. The reversal of 21862685197 is 79158626812.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21862685191) and next prime (21862685203).

It can be written as a sum of positive squares in 2 ways, for example, as 9161169796 + 12701515401 = 95714^2 + 112701^2 .

It is a cyclic number.

It is not a de Polignac number, because 21862685197 - 2³¹ = 19715201549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21862685191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1213668 + ... + 1231549.

It is an arithmetic number, because the mean of its divisors is an integer number (5466284839).

Almost surely, 2^21862685197 is an apocalyptic number.

It is an amenable number.

21862685197 is a deficient number, since it is larger than the sum of its proper divisors (2454159).

21862685197 is an equidigital number, since it uses as much as digits as its factorization.

21862685197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2454158.

The product of its digits is 2903040, while the sum is 55.

The spelling of 21862685197 in words is "twenty-one billion, eight hundred sixty-two million, six hundred eighty-five thousand, one hundred ninety-seven".