616551725221 has 4 divisors (see below), whose sum is σ = 616554047500. Its totient is φ = 616549402944.

The previous prime is 616551725183. The next prime is 616551725239. The reversal of 616551725221 is 122527155616.

616551725221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 320626605121 + 295925120100 = 566239^2 + 543990^2 .

It is a cyclic number.

It is not a de Polignac number, because 616551725221 - 2⁹ = 616551724709 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 (616551725281) 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, 702516 + ... + 1314013.

It is an arithmetic number, because the mean of its divisors is an integer number (154138511875).

Almost surely, 2^616551725221 is an apocalyptic number.

It is an amenable number.

616551725221 is a deficient number, since it is larger than the sum of its proper divisors (2322279).

616551725221 is a wasteful number, since it uses less digits than its factorization.

616551725221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2322278.

The product of its digits is 252000, while the sum is 43.

The spelling of 616551725221 in words is "six hundred sixteen billion, five hundred fifty-one million, seven hundred twenty-five thousand, two hundred twenty-one".