2505891 has 8 divisors (see below), whose sum is σ = 3517120. Its totient is φ = 1582632.

The previous prime is 2505863. The next prime is 2505901. The reversal of 2505891 is 1985052.

2505891 = T₃₄₄ + T₃₄₅ + ... + T₃₈₁.

2505891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2505891 - 2⁵ = 2505859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2505691) 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 7 ways as a sum of consecutive naturals, for example, 21925 + ... + 22038.

It is an arithmetic number, because the mean of its divisors is an integer number (439640).

2^2505891 is an apocalyptic number.

2505891 is a deficient number, since it is larger than the sum of its proper divisors (1011229).

2505891 is a wasteful number, since it uses less digits than its factorization.

2505891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43985.

The product of its (nonzero) digits is 3600, while the sum is 30.

The square root of 2505891 is about 1583.0006317118. Note that the first 3 decimals coincide. The cubic root of 2505891 is about 135.8274014330.

The spelling of 2505891 in words is "two million, five hundred five thousand, eight hundred ninety-one".