2620781 has 4 divisors (see below), whose sum is σ = 2734752. Its totient is φ = 2506812.

The previous prime is 2620741. The next prime is 2620811. The reversal of 2620781 is 1870262.

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 2620781 - 2¹⁸ = 2358637 is a prime.

It is a super-2 number, since 2×2620781² = 13736986099922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2620781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2620741) 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, 56951 + ... + 56996.

It is an arithmetic number, because the mean of its divisors is an integer number (683688).

2^2620781 is an apocalyptic number.

It is an amenable number.

2620781 is a deficient number, since it is larger than the sum of its proper divisors (113971).

2620781 is a wasteful number, since it uses less digits than its factorization.

2620781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113970.

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 2620781 is about 1618.8826393535. The cubic root of 2620781 is about 137.8722650558.

The spelling of 2620781 in words is "two million, six hundred twenty thousand, seven hundred eighty-one".