862890508561 has 9 divisors (see below), whose sum is σ = 865707778299. Its totient is φ = 860082386424.

The previous prime is 862890508549. The next prime is 862890508577. The reversal of 862890508561 is 165805098268.

The square root of 862890508561 is 928919.

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

It can be written as a sum of positive squares in only one way, i.e., 16041489025 + 846849019536 = 126655^2 + 920244^2 .

It is not a de Polignac number, because 862890508561 - 2¹³ = 862890500369 is a prime.

It is a super-2 number, since 2×862890508561² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 862890508496 and 862890508505.

It is not an unprimeable number, because it can be changed into a prime (862890509561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 322333555 + ... + 322336231.

Almost surely, 2^862890508561 is an apocalyptic number.

862890508561 is the 928919-th square number.

862890508561 is the 464460-th centered octagonal number.

It is an amenable number.

862890508561 is a deficient number, since it is larger than the sum of its proper divisors (2817269738).

862890508561 is an frugal number, since it uses more digits than its factorization.

862890508561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6048 (or 3024 counting only the distinct ones).

The product of its (nonzero) digits is 8294400, while the sum is 58.

The spelling of 862890508561 in words is "eight hundred sixty-two billion, eight hundred ninety million, five hundred eight thousand, five hundred sixty-one".