620660881 has 6 divisors (see below), whose sum is σ = 622986630. Its totient is φ = 618343776.

The previous prime is 620660869. The next prime is 620660891. The reversal of 620660881 is 188066026.

It can be written as a sum of positive squares in 3 ways, for example, as 54982225 + 565678656 = 7415^2 + 23784^2 .

It is not a de Polignac number, because 620660881 - 2¹¹ = 620658833 is a prime.

It is a super-2 number, since 2×620660881² = 770439858407392322, 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 620660881.

It is not an unprimeable number, because it can be changed into a prime (620660891) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 72685 + ... + 80773.

It is an arithmetic number, because the mean of its divisors is an integer number (103831105).

Almost surely, 2^620660881 is an apocalyptic number.

It is an amenable number.

620660881 is a deficient number, since it is larger than the sum of its proper divisors (2325749).

620660881 is an frugal number, since it uses more digits than its factorization.

620660881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8643 (or 8366 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 620660881 is about 24913.0664712315. The cubic root of 620660881 is about 853.0047662696.

The spelling of 620660881 in words is "six hundred twenty million, six hundred sixty thousand, eight hundred eighty-one".