13445981 has 4 divisors (see below), whose sum is σ = 13481472. Its totient is φ = 13410492.

The previous prime is 13445969. The next prime is 13446001. The reversal of 13445981 is 18954431.

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 13445981 - 2²² = 9251677 is a prime.

It is a super-2 number, since 2×13445981² = 361588810104722, 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 (13445921) 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, 17171 + ... + 17936.

It is an arithmetic number, because the mean of its divisors is an integer number (3370368).

Almost surely, 2^13445981 is an apocalyptic number.

It is an amenable number.

13445981 is a deficient number, since it is larger than the sum of its proper divisors (35491).

13445981 is an equidigital number, since it uses as much as digits as its factorization.

13445981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35490.

The product of its digits is 17280, while the sum is 35.

The square root of 13445981 is about 3666.8761909833. The cubic root of 13445981 is about 237.7921413298.

The spelling of 13445981 in words is "thirteen million, four hundred forty-five thousand, nine hundred eighty-one".