21020021202151 has 2 divisors, whose sum is σ = 21020021202152. Its totient is φ = 21020021202150.

The previous prime is 21020021202133. The next prime is 21020021202181. The reversal of 21020021202151 is 15120212002012.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21020021202151 - 2¹⁷ = 21020021071079 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21020021202121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510010601075 + 10510010601076.

It is an arithmetic number, because the mean of its divisors is an integer number (10510010601076).

Almost surely, 2^{21020021202151} is an apocalyptic number.

21020021202151 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020021202151 is an equidigital number, since it uses as much as digits as its factorization.

21020021202151 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 160, while the sum is 19.

Adding to 21020021202151 its reverse (15120212002012), we get a palindrome (36140233204163).

The spelling of 21020021202151 in words is "twenty-one trillion, twenty billion, twenty-one million, two hundred two thousand, one hundred fifty-one".