240781861 has 4 divisors (see below), whose sum is σ = 241080300. Its totient is φ = 240483424.

The previous prime is 240781847. The next prime is 240781873. The reversal of 240781861 is 168187042.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 138650625 + 102131236 = 11775^2 + 10106^2 .

It is a cyclic number.

It is not a de Polignac number, because 240781861 - 2¹⁹ = 240257573 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 240781861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (240781361) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 148006 + ... + 149623.

It is an arithmetic number, because the mean of its divisors is an integer number (60270075).

Almost surely, 2^240781861 is an apocalyptic number.

It is an amenable number.

240781861 is a deficient number, since it is larger than the sum of its proper divisors (298439).

240781861 is an equidigital number, since it uses as much as digits as its factorization.

240781861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298438.

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 240781861 is about 15517.1473215923. The cubic root of 240781861 is about 622.1206096695.

The spelling of 240781861 in words is "two hundred forty million, seven hundred eighty-one thousand, eight hundred sixty-one".