1957997 has 2 divisors, whose sum is σ = 1957998. Its totient is φ = 1957996.

The previous prime is 1957981. The next prime is 1957999. The reversal of 1957997 is 7997591.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1371241 + 586756 = 1171^2 + 766^2 .

It is a cyclic number.

It is not a de Polignac number, because 1957997 - 2⁴ = 1957981 is a prime.

Together with 1957999, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1957999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 978998 + 978999.

It is an arithmetic number, because the mean of its divisors is an integer number (978999).

2^1957997 is an apocalyptic number.

It is an amenable number.

1957997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1957997 is an equidigital number, since it uses as much as digits as its factorization.

1957997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 178605, while the sum is 47.

The square root of 1957997 is about 1399.2844600009. The cubic root of 1957997 is about 125.1038496980.

It can be divided in two parts, 195 and 7997, that added together give a 13-th power (8192 = 2¹³).

The spelling of 1957997 in words is "one million, nine hundred fifty-seven thousand, nine hundred ninety-seven".