201621651005 has 16 divisors (see below), whose sum is σ = 242726937024. Its totient is φ = 160776887040.

The previous prime is 201621650981. The next prime is 201621651013. The reversal of 201621651005 is 500156126102.

It is a happy number.

It is not a de Polignac number, because 201621651005 - 2³⁰ = 200547909181 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10875674 + ... + 10894196.

It is an arithmetic number, because the mean of its divisors is an integer number (15170433564).

Almost surely, 2^201621651005 is an apocalyptic number.

It is an amenable number.

201621651005 is a deficient number, since it is larger than the sum of its proper divisors (41105286019).

201621651005 is a wasteful number, since it uses less digits than its factorization.

201621651005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25436.

The product of its (nonzero) digits is 3600, while the sum is 29.

Adding to 201621651005 its reverse (500156126102), we get a palindrome (701777777107).

The spelling of 201621651005 in words is "two hundred one billion, six hundred twenty-one million, six hundred fifty-one thousand, five".