13420991 has 4 divisors (see below), whose sum is σ = 13706592. Its totient is φ = 13135392.

The previous prime is 13420987. The next prime is 13420999. The reversal of 13420991 is 19902431.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19902431 = 773 ⋅25747.

It is a cyclic number.

It is not a de Polignac number, because 13420991 - 2² = 13420987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13420999) 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, 142730 + ... + 142823.

It is an arithmetic number, because the mean of its divisors is an integer number (3426648).

Almost surely, 2^13420991 is an apocalyptic number.

13420991 is a deficient number, since it is larger than the sum of its proper divisors (285601).

13420991 is an equidigital number, since it uses as much as digits as its factorization.

13420991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285600.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 13420991 is about 3663.4670736885. The cubic root of 13420991 is about 237.6447339410.

The spelling of 13420991 in words is "thirteen million, four hundred twenty thousand, nine hundred ninety-one".