620447745221 has 4 divisors (see below), whose sum is σ = 620473927200. Its totient is φ = 620421563244.

The previous prime is 620447745193. The next prime is 620447745263. The reversal of 620447745221 is 122547744026.

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, and also an emirpimes, since its reverse is a distinct semiprime: 122547744026 = 2 ⋅61273872013.

It is a cyclic number.

It is not a de Polignac number, because 620447745221 - 2¹⁰ = 620447744197 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 (620447765221) 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, 13055411 + ... + 13102848.

It is an arithmetic number, because the mean of its divisors is an integer number (155118481800).

Almost surely, 2^620447745221 is an apocalyptic number.

It is an amenable number.

620447745221 is a deficient number, since it is larger than the sum of its proper divisors (26181979).

620447745221 is a wasteful number, since it uses less digits than its factorization.

620447745221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26181978.

The product of its (nonzero) digits is 752640, while the sum is 44.

The spelling of 620447745221 in words is "six hundred twenty billion, four hundred forty-seven million, seven hundred forty-five thousand, two hundred twenty-one".