261904190 has 16 divisors (see below), whose sum is σ = 471631680. Its totient is φ = 104716320.

The previous prime is 261904141. The next prime is 261904199. The reversal of 261904190 is 91409162.

It is a super-2 number, since 2×261904190² = 137187609479112200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261904199) 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, 28235 + ... + 36345.

It is an arithmetic number, because the mean of its divisors is an integer number (29476980).

Almost surely, 2^261904190 is an apocalyptic number.

261904190 is a deficient number, since it is larger than the sum of its proper divisors (209727490).

261904190 is a wasteful number, since it uses less digits than its factorization.

261904190 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11347.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 261904190 is about 16183.4542048353. The cubic root of 261904190 is about 639.8047825818.

The spelling of 261904190 in words is "two hundred sixty-one million, nine hundred four thousand, one hundred ninety".