1561203342 has 64 divisors (see below), whose sum is σ = 3624192000. Its totient is φ = 497526624.

The previous prime is 1561203299. The next prime is 1561203349. The reversal of 1561203342 is 2433021651.

1561203342 is a `hidden beast` number, since 1 + 5 + 612 + 0 + 3 + 3 + 42 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561203349) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 156459 + ... + 166137.

It is an arithmetic number, because the mean of its divisors is an integer number (56628000).

Almost surely, 2^1561203342 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1561203342, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1812096000).

1561203342 is an abundant number, since it is smaller than the sum of its proper divisors (2062988658).

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

1561203342 is a wasteful number, since it uses less digits than its factorization.

1561203342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9822 (or 9816 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 1561203342 is about 39512.0657774306. The cubic root of 1561203342 is about 1160.0761300610.

Adding to 1561203342 its reverse (2433021651), we get a palindrome (3994224993).

The spelling of 1561203342 in words is "one billion, five hundred sixty-one million, two hundred three thousand, three hundred forty-two".