61782913 has 4 divisors (see below), whose sum is σ = 65417220. Its totient is φ = 58148608.

The previous prime is 61782887. The next prime is 61782923. The reversal of 61782913 is 31928716.

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 54346384 + 7436529 = 7372^2 + 2727^2 .

It is a cyclic number.

It is not a de Polignac number, because 61782913 - 2⁵ = 61782881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61782923) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1817128 + ... + 1817161.

It is an arithmetic number, because the mean of its divisors is an integer number (16354305).

Almost surely, 2^61782913 is an apocalyptic number.

It is an amenable number.

61782913 is a deficient number, since it is larger than the sum of its proper divisors (3634307).

61782913 is a wasteful number, since it uses less digits than its factorization.

61782913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3634306.

The product of its digits is 18144, while the sum is 37.

The square root of 61782913 is about 7860.2107478108. The cubic root of 61782913 is about 395.3266816234.

The spelling of 61782913 in words is "sixty-one million, seven hundred eighty-two thousand, nine hundred thirteen".