261236198 has 4 divisors (see below), whose sum is σ = 391854300. Its totient is φ = 130618098.

The previous prime is 261236189. The next prime is 261236201. The reversal of 261236198 is 891632162.

It is a happy number.

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

It is a super-2 number, since 2×261236198² = 136488702290990408, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65309048 + ... + 65309051.

It is an arithmetic number, because the mean of its divisors is an integer number (97963575).

Almost surely, 2^261236198 is an apocalyptic number.

261236198 is a deficient number, since it is larger than the sum of its proper divisors (130618102).

261236198 is a wasteful number, since it uses less digits than its factorization.

261236198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130618101.

The product of its digits is 31104, while the sum is 38.

The square root of 261236198 is about 16162.8029128614. The cubic root of 261236198 is about 639.2603744110.

The spelling of 261236198 in words is "two hundred sixty-one million, two hundred thirty-six thousand, one hundred ninety-eight".