2620778 has 4 divisors (see below), whose sum is σ = 3931170. Its totient is φ = 1310388.

The previous prime is 2620741. The next prime is 2620811. The reversal of 2620778 is 8770262.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8770262 = 2 ⋅4385131.

It can be written as a sum of positive squares in only one way, i.e., 1723969 + 896809 = 1313^2 + 947^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655193 + ... + 655196.

2^2620778 is an apocalyptic number.

2620778 is a deficient number, since it is larger than the sum of its proper divisors (1310392).

2620778 is a wasteful number, since it uses less digits than its factorization.

2620778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1310391.

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 2620778 is about 1618.8817127882. The cubic root of 2620778 is about 137.8722124485.

The spelling of 2620778 in words is "two million, six hundred twenty thousand, seven hundred seventy-eight".