1864942565641 has 9 divisors (see below), whose sum is σ = 1869499836813. Its totient is φ = 1860396386700.

The previous prime is 1864942565543. The next prime is 1864942565659. The reversal of 1864942565641 is 1465652494681.

The square root of 1864942565641 is 1365629.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 1864942565641 - 2¹¹ = 1864942563593 is a prime.

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 1864942565641.

It is not an unprimeable number, because it can be changed into a prime (1864942565141) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 654134866 + ... + 654137716.

Almost surely, 2^{1864942565641} is an apocalyptic number.

1864942565641 is the 1365629-th square number.

1864942565641 is the 682815-th centered octagonal number.

It is an amenable number.

1864942565641 is a deficient number, since it is larger than the sum of its proper divisors (4557271172).

1864942565641 is an frugal number, since it uses more digits than its factorization.

1864942565641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6660 (or 3330 counting only the distinct ones).

The product of its digits is 49766400, while the sum is 61.

The spelling of 1864942565641 in words is "one trillion, eight hundred sixty-four billion, nine hundred forty-two million, five hundred sixty-five thousand, six hundred forty-one".