561155665650 has 48 divisors (see below), whose sum is σ = 1396415873664. Its totient is φ = 149130777280.

The previous prime is 561155665633. The next prime is 561155665717. The reversal of 561155665650 is 56566551165.

It is a junction number, because it is equal to n+sod(n) for n = 561155665593 and 561155665602.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6340074 + ... + 6427973.

It is an arithmetic number, because the mean of its divisors is an integer number (29091997368).

Almost surely, 2^561155665650 is an apocalyptic number.

561155665650 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

561155665650 is an abundant number, since it is smaller than the sum of its proper divisors (835260208014).

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

561155665650 is a wasteful number, since it uses less digits than its factorization.

561155665650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12768355 (or 12768350 counting only the distinct ones).

The product of its (nonzero) digits is 4050000, while the sum is 51.

The spelling of 561155665650 in words is "five hundred sixty-one billion, one hundred fifty-five million, six hundred sixty-five thousand, six hundred fifty".