2661945 has 64 divisors (see below), whose sum is σ = 5370624. Its totient is φ = 1105920.

The previous prime is 2661943. The next prime is 2661947. The reversal of 2661945 is 5491662.

2661945 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (2661943) and next prime (2661947).

It is not a de Polignac number, because 2661945 - 2¹ = 2661943 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

2661945 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2661943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 36429 + ... + 36501.

It is an arithmetic number, because the mean of its divisors is an integer number (83916).

2^2661945 is an apocalyptic number.

It is an amenable number.

2661945 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

2661945 is a wasteful number, since it uses less digits than its factorization.

2661945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122.

The product of its digits is 12960, while the sum is 33.

The square root of 2661945 is about 1631.5468120774. The cubic root of 2661945 is about 138.5903609962.

It can be divided in two parts, 266 and 1945, that added together give a triangular number (2211 = T₆₆).

The spelling of 2661945 in words is "two million, six hundred sixty-one thousand, nine hundred forty-five".