21021212111051 has 2 divisors, whose sum is σ = 21021212111052. Its totient is φ = 21021212111050.

The previous prime is 21021212111017. The next prime is 21021212111161. The reversal of 21021212111051 is 15011121212012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21021212111051 - 2³⁸ = 20746334204107 is a prime.

It is not a weakly prime, because it can be changed into another prime (21021212111951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510606055525 + 10510606055526.

It is an arithmetic number, because the mean of its divisors is an integer number (10510606055526).

Almost surely, 2^{21021212111051} is an apocalyptic number.

21021212111051 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021212111051 is an equidigital number, since it uses as much as digits as its factorization.

21021212111051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 80, while the sum is 20.

Adding to 21021212111051 its reverse (15011121212012), we get a palindrome (36032333323063).

The spelling of 21021212111051 in words is "twenty-one trillion, twenty-one billion, two hundred twelve million, one hundred eleven thousand, fifty-one".