7781221234 has 8 divisors (see below), whose sum is σ = 11673828828. Its totient is φ = 3889944960.

The previous prime is 7781221207. The next prime is 7781221267. The reversal of 7781221234 is 4321221877.

It can be written as a sum of positive squares in 2 ways, for example, as 7779769209 + 1452025 = 88203^2 + 1205^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 7781221193 and 7781221202.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 318087 + ... + 341674.

Almost surely, 2^7781221234 is an apocalyptic number.

7781221234 is a deficient number, since it is larger than the sum of its proper divisors (3892607594).

7781221234 is a wasteful number, since it uses less digits than its factorization.

7781221234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 665660.

The product of its digits is 37632, while the sum is 37.

The square root of 7781221234 is about 88211.2307702370. The cubic root of 7781221234 is about 1981.5996692338.

The spelling of 7781221234 in words is "seven billion, seven hundred eighty-one million, two hundred twenty-one thousand, two hundred thirty-four".