261122850 has 72 divisors (see below), whose sum is σ = 718711812. Its totient is φ = 67929600.

The previous prime is 261122843. The next prime is 261122857. The reversal of 261122850 is 58221162.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (261122843) and next prime (261122857).

It can be written as a sum of positive squares in 6 ways, for example, as 23068809 + 238054041 = 4803^2 + 15429^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261122857) 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 35 ways as a sum of consecutive naturals, for example, 11374 + ... + 25526.

Almost surely, 2^261122850 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261122850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (359355906).

261122850 is an abundant number, since it is smaller than the sum of its proper divisors (457588962).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261122850 is a wasteful number, since it uses less digits than its factorization.

261122850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14212 (or 14204 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 261122850 is about 16159.2960861542. The cubic root of 261122850 is about 639.1679046235.

The spelling of 261122850 in words is "two hundred sixty-one million, one hundred twenty-two thousand, eight hundred fifty".