19901117 has 4 divisors (see below), whose sum is σ = 19922076. Its totient is φ = 19880160.

The previous prime is 19901107. The next prime is 19901143. The reversal of 19901117 is 71110991.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17859076 + 2042041 = 4226^2 + 1429^2 .

It is a cyclic number.

It is not a de Polignac number, because 19901117 - 2¹⁶ = 19835581 is a prime.

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 19901117.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19901107) 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, 8984 + ... + 10977.

It is an arithmetic number, because the mean of its divisors is an integer number (4980519).

Almost surely, 2^19901117 is an apocalyptic number.

It is an amenable number.

19901117 is a deficient number, since it is larger than the sum of its proper divisors (20959).

19901117 is an equidigital number, since it uses as much as digits as its factorization.

19901117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20958.

The product of its (nonzero) digits is 567, while the sum is 29.

The square root of 19901117 is about 4461.0668006655. The cubic root of 19901117 is about 270.9936727779.

The spelling of 19901117 in words is "nineteen million, nine hundred one thousand, one hundred seventeen".