1801722221766 has 32 divisors (see below), whose sum is σ = 4009958673120. Its totient is φ = 599654346912.

The previous prime is 1801722221743. The next prime is 1801722221797. The reversal of 1801722221766 is 6671222271081.

It is a super-2 number, since 2×1801722221766² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25512385 + ... + 25582908.

It is an arithmetic number, because the mean of its divisors is an integer number (125311208535).

Almost surely, 2^{1801722221766} is an apocalyptic number.

1801722221766 is an abundant number, since it is smaller than the sum of its proper divisors (2208236451354).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1801722221766 is a wasteful number, since it uses less digits than its factorization.

1801722221766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51095957 (or 51095951 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The spelling of 1801722221766 in words is "one trillion, eight hundred one billion, seven hundred twenty-two million, two hundred twenty-one thousand, seven hundred sixty-six".