1491257 has 4 divisors (see below), whose sum is σ = 1578996. Its totient is φ = 1403520.

The previous prime is 1491247. The next prime is 1491271. The reversal of 1491257 is 7521941.

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

It can be written as a sum of positive squares in 2 ways, for example, as 817216 + 674041 = 904^2 + 821^2 .

It is not a de Polignac number, because 1491257 - 2⁴ = 1491241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1491227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43844 + ... + 43877.

It is an arithmetic number, because the mean of its divisors is an integer number (394749).

2^1491257 is an apocalyptic number.

1491257 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

1491257 is a deficient number, since it is larger than the sum of its proper divisors (87739).

1491257 is an equidigital number, since it uses as much as digits as its factorization.

1491257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87738.

The product of its digits is 2520, while the sum is 29.

The square root of 1491257 is about 1221.1703402884. The cubic root of 1491257 is about 114.2485854837.

The spelling of 1491257 in words is "one million, four hundred ninety-one thousand, two hundred fifty-seven".