1971869 has 2 divisors, whose sum is σ = 1971870. Its totient is φ = 1971868.

The previous prime is 1971857. The next prime is 1971887. The reversal of 1971869 is 9681791.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1092025 + 879844 = 1045^2 + 938^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1971869 is a prime.

It is a super-2 number, since 2×1971869² = 7776534706322, 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 (1971829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 985934 + 985935.

It is an arithmetic number, because the mean of its divisors is an integer number (985935).

2^1971869 is an apocalyptic number.

It is an amenable number.

1971869 is a deficient number, since it is larger than the sum of its proper divisors (1).

1971869 is an equidigital number, since it uses as much as digits as its factorization.

1971869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27216, while the sum is 41.

The square root of 1971869 is about 1404.2325306017. The cubic root of 1971869 is about 125.3985995959.

The spelling of 1971869 in words is "one million, nine hundred seventy-one thousand, eight hundred sixty-nine".