1945140561 has 240 divisors, whose sum is σ = 4089343104. Its totient is φ = 893555712.

The previous prime is 1945140541. The next prime is 1945140569. The reversal of 1945140561 is 1650415491.

1945140561 is a `hidden beast` number, since 1 + 9 + 4 + 51 + 40 + 561 = 666.

It is not a de Polignac number, because 1945140561 - 2⁹ = 1945140049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1945140569) by changing a digit.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 45235806 + ... + 45235848.

Almost surely, 2^1945140561 is an apocalyptic number.

It is an amenable number.

1945140561 is an abundant number, since it is smaller than the sum of its proper divisors (2144202543).

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

1945140561 is a wasteful number, since it uses less digits than its factorization.

1945140561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130 (or 102 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 1945140561 is about 44103.7476978998. The cubic root of 1945140561 is about 1248.2943266146.

The spelling of 1945140561 in words is "one billion, nine hundred forty-five million, one hundred forty thousand, five hundred sixty-one".