2123862865 has 4 divisors (see below), whose sum is σ = 2548635444. Its totient is φ = 1699090288.

The previous prime is 2123862859. The next prime is 2123862901. The reversal of 2123862865 is 5682683212.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1039675536 + 1084187329 = 32244^2 + 32927^2 .

It is a cyclic number.

It is not a de Polignac number, because 2123862865 - 2¹⁷ = 2123731793 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 212386282 + ... + 212386291.

It is an arithmetic number, because the mean of its divisors is an integer number (637158861).

Almost surely, 2^2123862865 is an apocalyptic number.

It is an amenable number.

2123862865 is a deficient number, since it is larger than the sum of its proper divisors (424772579).

2123862865 is an equidigital number, since it uses as much as digits as its factorization.

2123862865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 424772578.

The product of its digits is 276480, while the sum is 43.

The square root of 2123862865 is about 46085.3866751707. The cubic root of 2123862865 is about 1285.4114293688.

The spelling of 2123862865 in words is "two billion, one hundred twenty-three million, eight hundred sixty-two thousand, eight hundred sixty-five".