1299981 has 8 divisors (see below), whose sum is σ = 1738624. Its totient is φ = 864000.

The previous prime is 1299979. The next prime is 1299989. The reversal of 1299981 is 1899921.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1299981 - 2¹ = 1299979 is a prime.

It is a super-2 number, since 2×1299981² = 3379901200722, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1299989) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1356 + ... + 2106.

It is an arithmetic number, because the mean of its divisors is an integer number (217328).

2^1299981 is an apocalyptic number.

It is an amenable number.

1299981 is a deficient number, since it is larger than the sum of its proper divisors (438643).

1299981 is an equidigital number, since it uses as much as digits as its factorization.

1299981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1331.

The product of its digits is 11664, while the sum is 39.

The square root of 1299981 is about 1140.1670930175. The cubic root of 1299981 is about 109.1387565993.

The spelling of 1299981 in words is "one million, two hundred ninety-nine thousand, nine hundred eighty-one".