61539431 has 2 divisors, whose sum is σ = 61539432. Its totient is φ = 61539430.

The previous prime is 61539391. The next prime is 61539449. The reversal of 61539431 is 13493516.

61539431 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 61539431 - 2¹⁸ = 61277287 is a prime.

It is a super-2 number, since 2×61539431² = 7574203135607522, which contains 22 as substring.

It is a nialpdrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61539631) 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, 30769715 + 30769716.

It is an arithmetic number, because the mean of its divisors is an integer number (30769716).

Almost surely, 2^61539431 is an apocalyptic number.

61539431 is a deficient number, since it is larger than the sum of its proper divisors (1).

61539431 is an equidigital number, since it uses as much as digits as its factorization.

61539431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9720, while the sum is 32.

The square root of 61539431 is about 7844.7071965753. The cubic root of 61539431 is about 394.8066799565.

The spelling of 61539431 in words is "sixty-one million, five hundred thirty-nine thousand, four hundred thirty-one".