2778871225 has 27 divisors (see below), whose sum is σ = 3735857709. Its totient is φ = 2049559200.

The previous prime is 2778871177. The next prime is 2778871231. The reversal of 2778871225 is 5221788772.

It is a happy number.

The square root of 2778871225 is 52715.

It is a perfect power (a square), and thus also a powerful number.

2778871225 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 716258169 + 2062613056 = 26763^2 + 45416^2 .

It is not a de Polignac number, because 2778871225 - 2⁹ = 2778870713 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 3426070 + ... + 3426880.

Almost surely, 2^2778871225 is an apocalyptic number.

2778871225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

2778871225 is the 52715-th square number.

2778871225 is the 26358-th centered octagonal number.

It is an amenable number.

2778871225 is a deficient number, since it is larger than the sum of its proper divisors (956986484).

2778871225 is an frugal number, since it uses more digits than its factorization.

2778871225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1658 (or 829 counting only the distinct ones).

The product of its digits is 878080, while the sum is 49.

The cubic root of 2778871225 is about 1405.9055344602.

Multiplying 2778871225 by its sum of digits (49), we get a square (136164690025 = 369005²).

The spelling of 2778871225 in words is "two billion, seven hundred seventy-eight million, eight hundred seventy-one thousand, two hundred twenty-five".