2780398 has 4 divisors (see below), whose sum is σ = 4170600. Its totient is φ = 1390198.

The previous prime is 2780369. The next prime is 2780399. The reversal of 2780398 is 8930872.

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

It is a super-2 number, since 2×2780398² = 15461226076808, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2780399) 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, 695098 + ... + 695101.

It is an arithmetic number, because the mean of its divisors is an integer number (1042650).

2^2780398 is an apocalyptic number.

2780398 is a deficient number, since it is larger than the sum of its proper divisors (1390202).

2780398 is a wasteful number, since it uses less digits than its factorization.

2780398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1390201.

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 2780398 is about 1667.4525480505. The cubic root of 2780398 is about 140.6162966136.

The spelling of 2780398 in words is "two million, seven hundred eighty thousand, three hundred ninety-eight".