2151869 has 2 divisors, whose sum is σ = 2151870. Its totient is φ = 2151868.

The previous prime is 2151847. The next prime is 2151899. The reversal of 2151869 is 9681512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1836025 + 315844 = 1355^2 + 562^2 .

It is a cyclic number.

It is not a de Polignac number, because 2151869 - 2²⁰ = 1103293 is a prime.

It is a super-2 number, since 2×2151869² = 9261080386322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2151899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1075934 + 1075935.

It is an arithmetic number, because the mean of its divisors is an integer number (1075935).

2^2151869 is an apocalyptic number.

It is an amenable number.

2151869 is a deficient number, since it is larger than the sum of its proper divisors (1).

2151869 is an equidigital number, since it uses as much as digits as its factorization.

2151869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 32.

The square root of 2151869 is about 1466.9250151252. The cubic root of 2151869 is about 129.1036764437.

The spelling of 2151869 in words is "two million, one hundred fifty-one thousand, eight hundred sixty-nine".