1298991 has 8 divisors (see below), whose sum is σ = 1741824. Its totient is φ = 861080.

The previous prime is 1298989. The next prime is 1299007. The reversal of 1298991 is 1998921.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1298991 - 2¹ = 1298989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1298911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 561 + ... + 1706.

It is an arithmetic number, because the mean of its divisors is an integer number (217728).

2^1298991 is an apocalyptic number.

1298991 is a deficient number, since it is larger than the sum of its proper divisors (442833).

1298991 is a wasteful number, since it uses less digits than its factorization.

1298991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2461.

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

The square root of 1298991 is about 1139.7328634377. The cubic root of 1298991 is about 109.1110447049. Note that the first 3 decimals are identical.

The spelling of 1298991 in words is "one million, two hundred ninety-eight thousand, nine hundred ninety-one".