1516991 has 12 divisors (see below), whose sum is σ = 1790712. Its totient is φ = 1281168.

The previous prime is 1516987. The next prime is 1517023. The reversal of 1516991 is 1996151.

It is a happy number.

It is not a de Polignac number, because 1516991 - 2² = 1516987 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1516951) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3881 + ... + 4253.

It is an arithmetic number, because the mean of its divisors is an integer number (149226).

2^1516991 is an apocalyptic number.

1516991 is a deficient number, since it is larger than the sum of its proper divisors (273721).

1516991 is an equidigital number, since it uses as much as digits as its factorization.

1516991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 470 (or 463 counting only the distinct ones).

The product of its digits is 2430, while the sum is 32.

The square root of 1516991 is about 1231.6618854215. The cubic root of 1516991 is about 114.9020211466.

The spelling of 1516991 in words is "one million, five hundred sixteen thousand, nine hundred ninety-one".