1915997 has 2 divisors, whose sum is σ = 1915998. Its totient is φ = 1915996.

The previous prime is 1915993. The next prime is 1916021. The reversal of 1915997 is 7995191.

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., 1907161 + 8836 = 1381^2 + 94^2 .

It is a cyclic number.

It is not a de Polignac number, because 1915997 - 2² = 1915993 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 (1915993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 957998 + 957999.

It is an arithmetic number, because the mean of its divisors is an integer number (957999).

2^1915997 is an apocalyptic number.

It is an amenable number.

1915997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1915997 is an equidigital number, since it uses as much as digits as its factorization.

1915997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25515, while the sum is 41.

The square root of 1915997 is about 1384.1954341783. The cubic root of 1915997 is about 124.2028633916.

The spelling of 1915997 in words is "one million, nine hundred fifteen thousand, nine hundred ninety-seven".