261172250 has 16 divisors (see below), whose sum is σ = 488914920. Its totient is φ = 104468800.

The previous prime is 261172217. The next prime is 261172283. The reversal of 261172250 is 52271162.

It is an interprime number because it is at equal distance from previous prime (261172217) and next prime (261172283).

It can be written as a sum of positive squares in 4 ways, for example, as 105247081 + 155925169 = 10259^2 + 12487^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 522095 + ... + 522594.

Almost surely, 2^261172250 is an apocalyptic number.

261172250 is a deficient number, since it is larger than the sum of its proper divisors (227742670).

261172250 is a wasteful number, since it uses less digits than its factorization.

261172250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1044706 (or 1044696 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 261172250 is about 16160.8245457959. The cubic root of 261172250 is about 639.2082086458.

The spelling of 261172250 in words is "two hundred sixty-one million, one hundred seventy-two thousand, two hundred fifty".