261197066 has 32 divisors (see below), whose sum is σ = 450287040. Its totient is φ = 112627584.

The previous prime is 261197063. The next prime is 261197077. The reversal of 261197066 is 660791162.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is not an unprimeable number, because it can be changed into a prime (261197063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32441 + ... + 39683.

It is an arithmetic number, because the mean of its divisors is an integer number (14071470).

Almost surely, 2^261197066 is an apocalyptic number.

261197066 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

261197066 is a deficient number, since it is larger than the sum of its proper divisors (189089974).

261197066 is a wasteful number, since it uses less digits than its factorization.

261197066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7350.

The product of its (nonzero) digits is 27216, while the sum is 38.

The square root of 261197066 is about 16161.5923101655. The cubic root of 261197066 is about 639.2284533803.

The spelling of 261197066 in words is "two hundred sixty-one million, one hundred ninety-seven thousand, sixty-six".