261193451 has 16 divisors (see below), whose sum is σ = 277820928. Its totient is φ = 245044800.

The previous prime is 261193391. The next prime is 261193483. The reversal of 261193451 is 154391162.

It is a cyclic number.

It is not a de Polignac number, because 261193451 - 2¹⁴ = 261177067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261190451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 501071 + ... + 501591.

It is an arithmetic number, because the mean of its divisors is an integer number (17363808).

Almost surely, 2^261193451 is an apocalyptic number.

261193451 is a deficient number, since it is larger than the sum of its proper divisors (16627477).

261193451 is a wasteful number, since it uses less digits than its factorization.

261193451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 922.

The product of its digits is 6480, while the sum is 32.

The square root of 261193451 is about 16161.4804705510. The cubic root of 261193451 is about 639.2255043661.

The spelling of 261193451 in words is "two hundred sixty-one million, one hundred ninety-three thousand, four hundred fifty-one".