21577851367801 has 16 divisors (see below), whose sum is σ = 23564079000000. Its totient is φ = 19680718430016.

The previous prime is 21577851367799. The next prime is 21577851367819. The reversal of 21577851367801 is 10876315877512.

It is not a de Polignac number, because 21577851367801 - 2¹ = 21577851367799 is a prime.

It is a super-2 number, since 2×21577851367801² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21577851367801.

It is not an unprimeable number, because it can be changed into a prime (21577851367841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55912651 + ... + 56297248.

It is an arithmetic number, because the mean of its divisors is an integer number (1472754937500).

Almost surely, 2^{21577851367801} is an apocalyptic number.

It is an amenable number.

21577851367801 is a deficient number, since it is larger than the sum of its proper divisors (1986227632199).

21577851367801 is a wasteful number, since it uses less digits than its factorization.

21577851367801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112210296.

The product of its (nonzero) digits is 19756800, while the sum is 61.

The spelling of 21577851367801 in words is "twenty-one trillion, five hundred seventy-seven billion, eight hundred fifty-one million, three hundred sixty-seven thousand, eight hundred one".