261644199 has 8 divisors (see below), whose sum is σ = 355441392. Its totient is φ = 171138240.

The previous prime is 261644167. The next prime is 261644203. The reversal of 261644199 is 991446162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 261644199 - 2⁵ = 261644167 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 261644199.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261644099) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 822622 + ... + 822939.

It is an arithmetic number, because the mean of its divisors is an integer number (44430174).

Almost surely, 2^261644199 is an apocalyptic number.

261644199 is a deficient number, since it is larger than the sum of its proper divisors (93797193).

261644199 is a wasteful number, since it uses less digits than its factorization.

261644199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1645617.

The product of its digits is 93312, while the sum is 42.

The square root of 261644199 is about 16175.4195927030. The cubic root of 261644199 is about 639.5930021360.

The spelling of 261644199 in words is "two hundred sixty-one million, six hundred forty-four thousand, one hundred ninety-nine".