1257989 has 2 divisors, whose sum is σ = 1257990. Its totient is φ = 1257988.

The previous prime is 1257973. The next prime is 1258001. The reversal of 1257989 is 9897521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1085764 + 172225 = 1042^2 + 415^2 .

It is a cyclic number.

It is not a de Polignac number, because 1257989 - 2⁴ = 1257973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1257959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628994 + 628995.

It is an arithmetic number, because the mean of its divisors is an integer number (628995).

2^1257989 is an apocalyptic number.

It is an amenable number.

1257989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257989 is an equidigital number, since it uses as much as digits as its factorization.

1257989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45360, while the sum is 41.

The square root of 1257989 is about 1121.6010877313. The cubic root of 1257989 is about 107.9507377070.

The spelling of 1257989 in words is "one million, two hundred fifty-seven thousand, nine hundred eighty-nine".