1861622850564 has 36 divisors (see below), whose sum is σ = 4705814134476. Its totient is φ = 620534981568.

The previous prime is 1861622850557. The next prime is 1861622850569. The reversal of 1861622850564 is 4650582261681.

1861622850564 is a `hidden beast` number, since 1 + 8 + 6 + 1 + 6 + 2 + 28 + 50 + 564 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 96466148100 + 1765156702464 = 310590^2 + 1328592^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 1861622850564.

It is not an unprimeable number, because it can be changed into a prime (1861622850569) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5153782 + ... + 5503154.

It is an arithmetic number, because the mean of its divisors is an integer number (130717059291).

Almost surely, 2^{1861622850564} is an apocalyptic number.

It is an amenable number.

1861622850564 is an abundant number, since it is smaller than the sum of its proper divisors (2844191283912).

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

1861622850564 is a wasteful number, since it uses less digits than its factorization.

1861622850564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 497396 (or 497391 counting only the distinct ones).

The product of its (nonzero) digits is 5529600, while the sum is 54.

The spelling of 1861622850564 in words is "one trillion, eight hundred sixty-one billion, six hundred twenty-two million, eight hundred fifty thousand, five hundred sixty-four".