10002100221961 has 2 divisors, whose sum is σ = 10002100221962. Its totient is φ = 10002100221960.

The previous prime is 10002100221959. The next prime is 10002100221973. The reversal of 10002100221961 is 16912200120001.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6107476911561 + 3894623310400 = 2471331^2 + 1973480^2 .

It is a cyclic number.

It is not a de Polignac number, because 10002100221961 - 2¹ = 10002100221959 is a prime.

Together with 10002100221959, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (10002100221901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5001050110980 + 5001050110981.

It is an arithmetic number, because the mean of its divisors is an integer number (5001050110981).

Almost surely, 2^{10002100221961} is an apocalyptic number.

It is an amenable number.

10002100221961 is a deficient number, since it is larger than the sum of its proper divisors (1).

10002100221961 is an equidigital number, since it uses as much as digits as its factorization.

10002100221961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 25.

Adding to 10002100221961 its reverse (16912200120001), we get a palindrome (26914300341962).

The spelling of 10002100221961 in words is "ten trillion, two billion, one hundred million, two hundred twenty-one thousand, nine hundred sixty-one".