1013991 has 8 divisors (see below), whose sum is σ = 1474944. Its totient is φ = 614520.

The previous prime is 1013933. The next prime is 1013993. The reversal of 1013991 is 1993101.

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

It is not a de Polignac number, because 1013991 - 2¹⁰ = 1012967 is a prime.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1013993) 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, 15331 + ... + 15396.

It is an arithmetic number, because the mean of its divisors is an integer number (184368).

2^1013991 is an apocalyptic number.

1013991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1013991 is a deficient number, since it is larger than the sum of its proper divisors (460953).

1013991 is a wasteful number, since it uses less digits than its factorization.

1013991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30741.

The product of its (nonzero) digits is 243, while the sum is 24.

The square root of 1013991 is about 1006.9712011771. The cubic root of 1013991 is about 100.4642084375.

The spelling of 1013991 in words is "one million, thirteen thousand, nine hundred ninety-one".