1561356859554 has 48 divisors (see below), whose sum is σ = 3478562937720. Its totient is φ = 505774990080.

The previous prime is 1561356859553. The next prime is 1561356859583. The reversal of 1561356859554 is 4559586531651.

1561356859554 is a `hidden beast` number, since 1 + 5 + 6 + 1 + 35 + 6 + 8 + 595 + 5 + 4 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1544241155625 + 17115703929 = 1242675^2 + 130827^2 .

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1561356859491 and 1561356859500.

It is not an unprimeable number, because it can be changed into a prime (1561356859553) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 861867 + ... + 1966094.

Almost surely, 2^{1561356859554} is an apocalyptic number.

1561356859554 is an abundant number, since it is smaller than the sum of its proper divisors (1917206078166).

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

1561356859554 is a wasteful number, since it uses less digits than its factorization.

1561356859554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2828835 (or 2828832 counting only the distinct ones).

The product of its digits is 97200000, while the sum is 63.

The spelling of 1561356859554 in words is "one trillion, five hundred sixty-one billion, three hundred fifty-six million, eight hundred fifty-nine thousand, five hundred fifty-four".