7212778 has 4 divisors (see below), whose sum is σ = 10819170. Its totient is φ = 3606388.

The previous prime is 7212773. The next prime is 7212791. The reversal of 7212778 is 8772127.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 4941729 + 2271049 = 2223^2 + 1507^2 .

It is not an unprimeable number, because it can be changed into a prime (7212773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1803193 + ... + 1803196.

Almost surely, 2^7212778 is an apocalyptic number.

7212778 is a deficient number, since it is larger than the sum of its proper divisors (3606392).

7212778 is a wasteful number, since it uses less digits than its factorization.

7212778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3606391.

The product of its digits is 10976, while the sum is 34.

The square root of 7212778 is about 2685.6615572332. The cubic root of 7212778 is about 193.2120411089.

The spelling of 7212778 in words is "seven million, two hundred twelve thousand, seven hundred seventy-eight".