19872261 has 24 divisors (see below), whose sum is σ = 29450304. Its totient is φ = 12909120.

The previous prime is 19872241. The next prime is 19872263. The reversal of 19872261 is 16227891.

It is not a de Polignac number, because 19872261 - 2⁶ = 19872197 is a prime.

It is a super-3 number, since 3×19872261³ (a number of 23 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19872263) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 87430 + ... + 87656.

It is an arithmetic number, because the mean of its divisors is an integer number (1227096).

Almost surely, 2^19872261 is an apocalyptic number.

It is an amenable number.

19872261 is a deficient number, since it is larger than the sum of its proper divisors (9578043).

19872261 is a wasteful number, since it uses less digits than its factorization.

19872261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441 (or 438 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 19872261 is about 4457.8314234614. The cubic root of 19872261 is about 270.8626319599.

The spelling of 19872261 in words is "nineteen million, eight hundred seventy-two thousand, two hundred sixty-one".