61015891 has 2 divisors, whose sum is σ = 61015892. Its totient is φ = 61015890.

The previous prime is 61015811. The next prime is 61015931. The reversal of 61015891 is 19851016.

61015891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61015891 - 2²⁵ = 27461459 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (61015811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30507945 + 30507946.

It is an arithmetic number, because the mean of its divisors is an integer number (30507946).

Almost surely, 2^61015891 is an apocalyptic number.

61015891 is a deficient number, since it is larger than the sum of its proper divisors (1).

61015891 is an equidigital number, since it uses as much as digits as its factorization.

61015891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 31.

The square root of 61015891 is about 7811.2669266899. The cubic root of 61015891 is about 393.6838983351.

The spelling of 61015891 in words is "sixty-one million, fifteen thousand, eight hundred ninety-one".