1315981 has 4 divisors (see below), whose sum is σ = 1358464. Its totient is φ = 1273500.

The previous prime is 1315969. The next prime is 1316009. The reversal of 1315981 is 1895131.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1315981 - 2⁵ = 1315949 is a prime.

It is a super-2 number, since 2×1315981² = 3463611984722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1315901) 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, 21195 + ... + 21256.

It is an arithmetic number, because the mean of its divisors is an integer number (339616).

2^1315981 is an apocalyptic number.

It is an amenable number.

1315981 is a deficient number, since it is larger than the sum of its proper divisors (42483).

1315981 is an equidigital number, since it uses as much as digits as its factorization.

1315981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42482.

The product of its digits is 1080, while the sum is 28.

The square root of 1315981 is about 1147.1621507006. The cubic root of 1315981 is about 109.5846873753.

The spelling of 1315981 in words is "one million, three hundred fifteen thousand, nine hundred eighty-one".