261226172 has 6 divisors (see below), whose sum is σ = 457145808. Its totient is φ = 130613084.

The previous prime is 261226159. The next prime is 261226223. The reversal of 261226172 is 271622162.

It is a happy number.

It is a super-2 number, since 2×261226172² = 136478225875547168, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 32653268 + ... + 32653275.

It is an arithmetic number, because the mean of its divisors is an integer number (76190968).

Almost surely, 2^261226172 is an apocalyptic number.

It is an amenable number.

261226172 is a deficient number, since it is larger than the sum of its proper divisors (195919636).

261226172 is a wasteful number, since it uses less digits than its factorization.

261226172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65306547 (or 65306545 counting only the distinct ones).

The product of its digits is 4032, while the sum is 29.

The square root of 261226172 is about 16162.4927532853. The cubic root of 261226172 is about 639.2521962354.

The spelling of 261226172 in words is "two hundred sixty-one million, two hundred twenty-six thousand, one hundred seventy-two".