101621640121 has 2 divisors, whose sum is σ = 101621640122. Its totient is φ = 101621640120.

The previous prime is 101621640119. The next prime is 101621640137. The reversal of 101621640121 is 121046126101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 98319873600 + 3301766521 = 313560^2 + 57461^2 .

It is an emirp because it is prime and its reverse (121046126101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 101621640121 - 2¹ = 101621640119 is a prime.

Together with 101621640119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (101621640191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50810820060 + 50810820061.

It is an arithmetic number, because the mean of its divisors is an integer number (50810820061).

Almost surely, 2^101621640121 is an apocalyptic number.

It is an amenable number.

101621640121 is a deficient number, since it is larger than the sum of its proper divisors (1).

101621640121 is an equidigital number, since it uses as much as digits as its factorization.

101621640121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 25.

Adding to 101621640121 its reverse (121046126101), we get a palindrome (222667766222).

The spelling of 101621640121 in words is "one hundred one billion, six hundred twenty-one million, six hundred forty thousand, one hundred twenty-one".