2778132321 has 6 divisors (see below), whose sum is σ = 4012857810. Its totient is φ = 1852088208.

The previous prime is 2778132293. The next prime is 2778132359. The reversal of 2778132321 is 1232318772.

It can be written as a sum of positive squares in only one way, i.e., 2360502225 + 417630096 = 48585^2 + 20436^2 .

It is not a de Polignac number, because 2778132321 - 2⁹ = 2778131809 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2778130321) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 154340676 + ... + 154340693.

It is an arithmetic number, because the mean of its divisors is an integer number (668809635).

Almost surely, 2^2778132321 is an apocalyptic number.

It is an amenable number.

2778132321 is a deficient number, since it is larger than the sum of its proper divisors (1234725489).

2778132321 is a wasteful number, since it uses less digits than its factorization.

2778132321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308681375 (or 308681372 counting only the distinct ones).

The product of its digits is 28224, while the sum is 36.

The square root of 2778132321 is about 52707.9910544881. The cubic root of 2778132321 is about 1405.7809129589.

The spelling of 2778132321 in words is "two billion, seven hundred seventy-eight million, one hundred thirty-two thousand, three hundred twenty-one".