620265781 has 4 divisors (see below), whose sum is σ = 621271692. Its totient is φ = 619259872.

The previous prime is 620265769. The next prime is 620265799. The reversal of 620265781 is 187562026.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 213598225 + 406667556 = 14615^2 + 20166^2 .

It is a cyclic number.

It is not a de Polignac number, because 620265781 - 2¹¹ = 620263733 is a prime.

It is a super-2 number, since 2×620265781² = 769459278159079922, 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 620265781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (620263781) 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 in 3 ways as a sum of consecutive naturals, for example, 502030 + ... + 503263.

It is an arithmetic number, because the mean of its divisors is an integer number (155317923).

Almost surely, 2^620265781 is an apocalyptic number.

It is an amenable number.

620265781 is a deficient number, since it is larger than the sum of its proper divisors (1005911).

620265781 is a wasteful number, since it uses less digits than its factorization.

620265781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1005910.

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 620265781 is about 24905.1356350452. The cubic root of 620265781 is about 852.8237260630.

The spelling of 620265781 in words is "six hundred twenty million, two hundred sixty-five thousand, seven hundred eighty-one".