21042534701 has 2 divisors, whose sum is σ = 21042534702. Its totient is φ = 21042534700.

The previous prime is 21042534697. The next prime is 21042534727. The reversal of 21042534701 is 10743524012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20584788676 + 457746025 = 143474^2 + 21395^2 .

It is a cyclic number.

It is not a de Polignac number, because 21042534701 - 2² = 21042534697 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21042534001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10521267350 + 10521267351.

It is an arithmetic number, because the mean of its divisors is an integer number (10521267351).

Almost surely, 2^21042534701 is an apocalyptic number.

It is an amenable number.

21042534701 is a deficient number, since it is larger than the sum of its proper divisors (1).

21042534701 is an equidigital number, since it uses as much as digits as its factorization.

21042534701 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 29.

The spelling of 21042534701 in words is "twenty-one billion, forty-two million, five hundred thirty-four thousand, seven hundred one".