21986523701 has 2 divisors, whose sum is σ = 21986523702. Its totient is φ = 21986523700.

The previous prime is 21986523679. The next prime is 21986523751. The reversal of 21986523701 is 10732568912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18368380900 + 3618142801 = 135530^2 + 60151^2 .

It is a cyclic number.

It is not a de Polignac number, because 21986523701 - 2¹⁴ = 21986507317 is a prime.

It is a super-3 number, since 3×21986523701³ (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 (21986523751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10993261850 + 10993261851.

It is an arithmetic number, because the mean of its divisors is an integer number (10993261851).

Almost surely, 2^21986523701 is an apocalyptic number.

It is an amenable number.

21986523701 is a deficient number, since it is larger than the sum of its proper divisors (1).

21986523701 is an equidigital number, since it uses as much as digits as its factorization.

21986523701 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 44.

The spelling of 21986523701 in words is "twenty-one billion, nine hundred eighty-six million, five hundred twenty-three thousand, seven hundred one".