620618821 has 16 divisors (see below), whose sum is σ = 671328000. Its totient is φ = 571973248.

The previous prime is 620618809. The next prime is 620618827. The reversal of 620618821 is 128816026.

It is a cyclic number.

It is not a de Polignac number, because 620618821 - 2⁷ = 620618693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (620618827) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 591105 + ... + 592153.

It is an arithmetic number, because the mean of its divisors is an integer number (41958000).

Almost surely, 2^620618821 is an apocalyptic number.

It is an amenable number.

620618821 is a deficient number, since it is larger than the sum of its proper divisors (50709179).

620618821 is a wasteful number, since it uses less digits than its factorization.

620618821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1988.

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 620618821 is about 24912.2223215834. Note that the first 3 decimals coincide. The cubic root of 620618821 is about 852.9854974589.

The spelling of 620618821 in words is "six hundred twenty million, six hundred eighteen thousand, eight hundred twenty-one".