1257155 has 4 divisors (see below), whose sum is σ = 1508592. Its totient is φ = 1005720.

The previous prime is 1257131. The next prime is 1257163. The reversal of 1257155 is 5517521.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1257155 - 2¹² = 1253059 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 125711 + ... + 125720.

It is an arithmetic number, because the mean of its divisors is an integer number (377148).

2^1257155 is an apocalyptic number.

1257155 is a deficient number, since it is larger than the sum of its proper divisors (251437).

1257155 is an equidigital number, since it uses as much as digits as its factorization.

1257155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251436.

The product of its digits is 1750, while the sum is 26.

The square root of 1257155 is about 1121.2292361511. The cubic root of 1257155 is about 107.9268766562.

The spelling of 1257155 in words is "one million, two hundred fifty-seven thousand, one hundred fifty-five".