2261781 has 12 divisors (see below), whose sum is σ = 3337152. Its totient is φ = 1475496.

The previous prime is 2261771. The next prime is 2261789. The reversal of 2261781 is 1871622.

It is not a de Polignac number, because 2261781 - 2⁶ = 2261717 is a prime.

It is a super-2 number, since 2×2261781² = 10231306583922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2261789) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2251 + ... + 3096.

It is an arithmetic number, because the mean of its divisors is an integer number (278096).

2^2261781 is an apocalyptic number.

It is an amenable number.

2261781 is a deficient number, since it is larger than the sum of its proper divisors (1075371).

2261781 is a wasteful number, since it uses less digits than its factorization.

2261781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5400 (or 5397 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 2261781 is about 1503.9218729708. The cubic root of 2261781 is about 131.2653750696.

The spelling of 2261781 in words is "two million, two hundred sixty-one thousand, seven hundred eighty-one".