2141781 has 4 divisors (see below), whose sum is σ = 2855712. Its totient is φ = 1427852.

The previous prime is 2141753. The next prime is 2141791. The reversal of 2141781 is 1871412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2141781 - 2⁵ = 2141749 is a prime.

It is a super-2 number, since 2×2141781² = 9174451703922, which contains 22 as substring.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2141731) 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, 356961 + ... + 356966.

It is an arithmetic number, because the mean of its divisors is an integer number (713928).

2^2141781 is an apocalyptic number.

It is an amenable number.

2141781 is a deficient number, since it is larger than the sum of its proper divisors (713931).

2141781 is an equidigital number, since it uses as much as digits as its factorization.

2141781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713930.

The product of its digits is 448, while the sum is 24.

The square root of 2141781 is about 1463.4824905000. The cubic root of 2141781 is about 128.9016135816.

The spelling of 2141781 in words is "two million, one hundred forty-one thousand, seven hundred eighty-one".