21102101029 has 2 divisors, whose sum is σ = 21102101030. Its totient is φ = 21102101028.

The previous prime is 21102100951. The next prime is 21102101057. The reversal of 21102101029 is 92010120112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16282270404 + 4819830625 = 127602^2 + 69425^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21102101029 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21102100997 and 21102101015.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21102101929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10551050514 + 10551050515.

It is an arithmetic number, because the mean of its divisors is an integer number (10551050515).

Almost surely, 2^21102101029 is an apocalyptic number.

It is an amenable number.

21102101029 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102101029 is an equidigital number, since it uses as much as digits as its factorization.

21102101029 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 21102101029 in words is "twenty-one billion, one hundred two million, one hundred one thousand, twenty-nine".