61783945 has 4 divisors (see below), whose sum is σ = 74140740. Its totient is φ = 49427152.

The previous prime is 61783937. The next prime is 61783951. The reversal of 61783945 is 54938716.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 32764176 + 29019769 = 5724^2 + 5387^2 .

It is a cyclic number.

It is not a de Polignac number, because 61783945 - 2³ = 61783937 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6178390 + ... + 6178399.

It is an arithmetic number, because the mean of its divisors is an integer number (18535185).

Almost surely, 2^61783945 is an apocalyptic number.

It is an amenable number.

61783945 is a deficient number, since it is larger than the sum of its proper divisors (12356795).

61783945 is a wasteful number, since it uses less digits than its factorization.

61783945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12356794.

The product of its digits is 181440, while the sum is 43.

The square root of 61783945 is about 7860.2763946314. The cubic root of 61783945 is about 395.3288827437.

The spelling of 61783945 in words is "sixty-one million, seven hundred eighty-three thousand, nine hundred forty-five".