61005831 has 4 divisors (see below), whose sum is σ = 81341112. Its totient is φ = 40670552.

The previous prime is 61005817. The next prime is 61005839. The reversal of 61005831 is 13850016.

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

It is a cyclic number.

It is not a de Polignac number, because 61005831 - 2⁹ = 61005319 is a prime.

It is a super-2 number, since 2×61005831² = 7443422832001122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61005839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10167636 + ... + 10167641.

It is an arithmetic number, because the mean of its divisors is an integer number (20335278).

Almost surely, 2^61005831 is an apocalyptic number.

61005831 is a deficient number, since it is larger than the sum of its proper divisors (20335281).

61005831 is a wasteful number, since it uses less digits than its factorization.

61005831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20335280.

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 61005831 is about 7810.6229585098. The cubic root of 61005831 is about 393.6622609243.

Adding to 61005831 its reverse (13850016), we get a palindrome (74855847).

The spelling of 61005831 in words is "sixty-one million, five thousand, eight hundred thirty-one".