21575687212801 has 6 divisors (see below), whose sum is σ = 21852254272002. Its totient is φ = 21302577241920.

The previous prime is 21575687212787. The next prime is 21575687212889. The reversal of 21575687212801 is 10821278657512.

It can be written as a sum of positive squares in only one way, i.e., 18759076880625 + 2816610332176 = 4331175^2 + 1678276^2 .

It is not a de Polignac number, because 21575687212801 - 2¹³ = 21575687204609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21575687216801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1728537840 + ... + 1728550321.

It is an arithmetic number, because the mean of its divisors is an integer number (3642042378667).

Almost surely, 2^{21575687212801} is an apocalyptic number.

It is an amenable number.

21575687212801 is a deficient number, since it is larger than the sum of its proper divisors (276567059201).

21575687212801 is an frugal number, since it uses more digits than its factorization.

21575687212801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3457088319 (or 3457088240 counting only the distinct ones).

The product of its (nonzero) digits is 3763200, while the sum is 55.

The spelling of 21575687212801 in words is "twenty-one trillion, five hundred seventy-five billion, six hundred eighty-seven million, two hundred twelve thousand, eight hundred one".