621450186221 has 4 divisors (see below), whose sum is σ = 621472321344. Its totient is φ = 621428051100.

The previous prime is 621450186193. The next prime is 621450186229. The reversal of 621450186221 is 122681054126.

It is a happy number.

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: 122681054126 = 2 ⋅61340527063.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-621450186221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621450186229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11025395 + ... + 11081616.

It is an arithmetic number, because the mean of its divisors is an integer number (155368080336).

Almost surely, 2^621450186221 is an apocalyptic number.

It is an amenable number.

621450186221 is a deficient number, since it is larger than the sum of its proper divisors (22135123).

621450186221 is a wasteful number, since it uses less digits than its factorization.

621450186221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22135122.

The product of its (nonzero) digits is 46080, while the sum is 38.

The spelling of 621450186221 in words is "six hundred twenty-one billion, four hundred fifty million, one hundred eighty-six thousand, two hundred twenty-one".