1251491 has 4 divisors (see below), whose sum is σ = 1263984. Its totient is φ = 1239000.

The previous prime is 1251463. The next prime is 1251527. The reversal of 1251491 is 1941521.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1941521 = 29 ⋅66949.

It is a cyclic number.

It is not a de Polignac number, because 1251491 - 2⁶ = 1251427 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1251431) 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, 6095 + ... + 6296.

It is an arithmetic number, because the mean of its divisors is an integer number (315996).

2^1251491 is an apocalyptic number.

1251491 is a deficient number, since it is larger than the sum of its proper divisors (12493).

1251491 is a wasteful number, since it uses less digits than its factorization.

1251491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12492.

The product of its digits is 360, while the sum is 23.

The square root of 1251491 is about 1118.7005855009. The cubic root of 1251491 is about 107.7645476452.

The spelling of 1251491 in words is "one million, two hundred fifty-one thousand, four hundred ninety-one".