21267858061 has 2 divisors, whose sum is σ = 21267858062. Its totient is φ = 21267858060.

The previous prime is 21267858019. The next prime is 21267858083. The reversal of 21267858061 is 16085876212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20997748836 + 270109225 = 144906^2 + 16435^2 .

It is a cyclic number.

It is not a de Polignac number, because 21267858061 - 2⁹ = 21267857549 is a prime.

It is a super-3 number, since 3×21267858061³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21267858461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10633929030 + 10633929031.

It is an arithmetic number, because the mean of its divisors is an integer number (10633929031).

Almost surely, 2^21267858061 is an apocalyptic number.

It is an amenable number.

21267858061 is a deficient number, since it is larger than the sum of its proper divisors (1).

21267858061 is an equidigital number, since it uses as much as digits as its factorization.

21267858061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 322560, while the sum is 46.

The spelling of 21267858061 in words is "twenty-one billion, two hundred sixty-seven million, eight hundred fifty-eight thousand, sixty-one".