2779481221 has 4 divisors (see below), whose sum is σ = 3032161344. Its totient is φ = 2526801100.

The previous prime is 2779481189. The next prime is 2779481261. The reversal of 2779481221 is 1221849772.

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 2779481221 - 2⁵ = 2779481189 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 (2779481261) 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, 126340045 + ... + 126340066.

It is an arithmetic number, because the mean of its divisors is an integer number (758040336).

Almost surely, 2^2779481221 is an apocalyptic number.

It is an amenable number.

2779481221 is a deficient number, since it is larger than the sum of its proper divisors (252680123).

2779481221 is a wasteful number, since it uses less digits than its factorization.

2779481221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252680122.

The product of its digits is 112896, while the sum is 43.

The square root of 2779481221 is about 52720.7854740424. The cubic root of 2779481221 is about 1406.0083980500.

The spelling of 2779481221 in words is "two billion, seven hundred seventy-nine million, four hundred eighty-one thousand, two hundred twenty-one".