61539637 has 2 divisors, whose sum is σ = 61539638. Its totient is φ = 61539636.

The previous prime is 61539631. The next prime is 61539641. The reversal of 61539637 is 73693516.

61539637 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 can be written as a sum of positive squares in only one way, i.e., 42954916 + 18584721 = 6554^2 + 4311^2 .

It is a cyclic number.

It is not a de Polignac number, because 61539637 - 2³ = 61539629 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61539637.

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, 30769818 + 30769819.

It is an arithmetic number, because the mean of its divisors is an integer number (30769819).

Almost surely, 2^61539637 is an apocalyptic number.

It is an amenable number.

61539637 is a deficient number, since it is larger than the sum of its proper divisors (1).

61539637 is an equidigital number, since it uses as much as digits as its factorization.

61539637 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 102060, while the sum is 40.

The square root of 61539637 is about 7844.7203264361. The cubic root of 61539637 is about 394.8071204875.

The spelling of 61539637 in words is "sixty-one million, five hundred thirty-nine thousand, six hundred thirty-seven".