13365991 has 16 divisors (see below), whose sum is σ = 14553088. Its totient is φ = 12247200.

The previous prime is 13365983. The next prime is 13365997. The reversal of 13365991 is 19956331.

It is a cyclic number.

It is not a de Polignac number, because 13365991 - 2³ = 13365983 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13365991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13365997) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49186 + ... + 49456.

It is an arithmetic number, because the mean of its divisors is an integer number (909568).

Almost surely, 2^13365991 is an apocalyptic number.

13365991 is a deficient number, since it is larger than the sum of its proper divisors (1187097).

13365991 is a wasteful number, since it uses less digits than its factorization.

13365991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382.

The product of its digits is 21870, while the sum is 37.

The square root of 13365991 is about 3655.9528169822. The cubic root of 13365991 is about 237.3196621777.

The spelling of 13365991 in words is "thirteen million, three hundred sixty-five thousand, nine hundred ninety-one".