61147839 has 4 divisors (see below), whose sum is σ = 81530456. Its totient is φ = 40765224.

The previous prime is 61147829. The next prime is 61147859. The reversal of 61147839 is 93874116.

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

It is not a de Polignac number, because 61147839 - 2¹³ = 61139647 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61147797 and 61147806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61147829) 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, 10191304 + ... + 10191309.

It is an arithmetic number, because the mean of its divisors is an integer number (20382614).

Almost surely, 2^61147839 is an apocalyptic number.

61147839 is a deficient number, since it is larger than the sum of its proper divisors (20382617).

61147839 is a wasteful number, since it uses less digits than its factorization.

61147839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20382616.

The product of its digits is 36288, while the sum is 39.

The square root of 61147839 is about 7819.7083705212. The cubic root of 61147839 is about 393.9674769379.

The spelling of 61147839 in words is "sixty-one million, one hundred forty-seven thousand, eight hundred thirty-nine".