2581949 has 4 divisors (see below), whose sum is σ = 2599200. Its totient is φ = 2564700.

The previous prime is 2581939. The next prime is 2581951. The reversal of 2581949 is 9491852.

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 2581949 - 2⁴ = 2581933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2581919) 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, 8399 + ... + 8700.

It is an arithmetic number, because the mean of its divisors is an integer number (649800).

2^2581949 is an apocalyptic number.

It is an amenable number.

2581949 is a deficient number, since it is larger than the sum of its proper divisors (17251).

2581949 is a wasteful number, since it uses less digits than its factorization.

2581949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17250.

The product of its digits is 25920, while the sum is 38.

The square root of 2581949 is about 1606.8444230852. The cubic root of 2581949 is about 137.1879247448.

Subtracting 2581949 from its reverse (9491852), we obtain a triangular number (6909903 = T₃₇₁₇).

The spelling of 2581949 in words is "two million, five hundred eighty-one thousand, nine hundred forty-nine".