191261238 has 64 divisors (see below), whose sum is σ = 460062720. Its totient is φ = 51825312.

The previous prime is 191261233. The next prime is 191261243. The reversal of 191261238 is 832162191.

It is an interprime number because it is at equal distance from previous prime (191261233) and next prime (191261243).

It is a super-2 number, since 2×191261238² = 73161722322585288, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 191261199 and 191261208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191261233) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 121903 + ... + 123461.

It is an arithmetic number, because the mean of its divisors is an integer number (7188480).

Almost surely, 2^191261238 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 191261238, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (230031360).

191261238 is an abundant number, since it is smaller than the sum of its proper divisors (268801482).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

191261238 is a wasteful number, since it uses less digits than its factorization.

191261238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1721.

The product of its digits is 5184, while the sum is 33.

The square root of 191261238 is about 13829.7229907182. The cubic root of 191261238 is about 576.1589609976.

The spelling of 191261238 in words is "one hundred ninety-one million, two hundred sixty-one thousand, two hundred thirty-eight".