2557890 has 48 divisors (see below), whose sum is σ = 6742008. Its totient is φ = 672768.

The previous prime is 2557889. The next prime is 2557897. The reversal of 2557890 is 987552.

It can be written as a sum of positive squares in 4 ways, for example, as 2442969 + 114921 = 1563^2 + 339^2 .

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (2557897) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8584 + ... + 8876.

2^2557890 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2557890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3371004).

2557890 is an abundant number, since it is smaller than the sum of its proper divisors (4184118).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2557890 is a wasteful number, since it uses less digits than its factorization.

2557890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403 (or 400 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 36.

The square root of 2557890 is about 1599.3404890767. The cubic root of 2557890 is about 136.7604815573.

The spelling of 2557890 in words is "two million, five hundred fifty-seven thousand, eight hundred ninety".