2142661 has 4 divisors (see below), whose sum is σ = 2151072. Its totient is φ = 2134252.

The previous prime is 2142659. The next prime is 2142667. The reversal of 2142661 is 1662412.

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 2142661 - 2¹ = 2142659 is a prime.

It is a Duffinian number.

2142661 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2142667) 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, 3811 + ... + 4336.

It is an arithmetic number, because the mean of its divisors is an integer number (537768).

2^2142661 is an apocalyptic number.

It is an amenable number.

2142661 is a deficient number, since it is larger than the sum of its proper divisors (8411).

2142661 is an equidigital number, since it uses as much as digits as its factorization.

2142661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8410.

The product of its digits is 576, while the sum is 22.

The square root of 2142661 is about 1463.7831123496. The cubic root of 2142661 is about 128.9192652289.

Subtracting from 2142661 its reverse (1662412), we obtain a square (480249 = 693²).

The spelling of 2142661 in words is "two million, one hundred forty-two thousand, six hundred sixty-one".