2781250 has 28 divisors (see below), whose sum is σ = 5273370. Its totient is φ = 1100000.

The previous prime is 2781221. The next prime is 2781271. The reversal of 2781250 is 521872.

It can be written as a sum of positive squares in 7 ways, for example, as 1929321 + 851929 = 1389^2 + 923^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is an Ulam number.

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 31206 + ... + 31294.

2^2781250 is an apocalyptic number.

2781250 is a deficient number, since it is larger than the sum of its proper divisors (2492120).

2781250 is an frugal number, since it uses more digits than its factorization.

2781250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121 (or 96 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 2781250 is about 1667.7080080158. The cubic root of 2781250 is about 140.6306582085.

It can be divided in two parts, 2 and 781250, that multiplied together give a square (1562500 = 1250²).

The spelling of 2781250 in words is "two million, seven hundred eighty-one thousand, two hundred fifty".