1561245966 has 48 divisors (see below), whose sum is σ = 4093356384. Its totient is φ = 419830272.

The previous prime is 1561245937. The next prime is 1561245967. The reversal of 1561245966 is 6695421651.

1561245966 is a `hidden beast` number, since 1 + 56 + 1 + 2 + 4 + 596 + 6 = 666.

1561245966 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561245967) 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, 362295 + ... + 366578.

It is an arithmetic number, because the mean of its divisors is an integer number (85278258).

Almost surely, 2^1561245966 is an apocalyptic number.

1561245966 is an abundant number, since it is smaller than the sum of its proper divisors (2532110418).

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

1561245966 is a wasteful number, since it uses less digits than its factorization.

1561245966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 728905 (or 728902 counting only the distinct ones).

The product of its digits is 388800, while the sum is 45.

The square root of 1561245966 is about 39512.6051532925. The cubic root of 1561245966 is about 1160.0866874376.

The spelling of 1561245966 in words is "one billion, five hundred sixty-one million, two hundred forty-five thousand, nine hundred sixty-six".