21220500101 has 2 divisors, whose sum is σ = 21220500102. Its totient is φ = 21220500100.

The previous prime is 21220500001. The next prime is 21220500173. The reversal of 21220500101 is 10100502212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16589697601 + 4630802500 = 128801^2 + 68050^2 .

It is a cyclic number.

It is not a de Polignac number, because 21220500101 - 2²² = 21216305797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21220500001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610250050 + 10610250051.

It is an arithmetic number, because the mean of its divisors is an integer number (10610250051).

Almost surely, 2^21220500101 is an apocalyptic number.

It is an amenable number.

21220500101 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220500101 is an equidigital number, since it uses as much as digits as its factorization.

21220500101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40, while the sum is 14.

The spelling of 21220500101 in words is "twenty-one billion, two hundred twenty million, five hundred thousand, one hundred one".