61606591 has 4 divisors (see below), whose sum is σ = 63271672. Its totient is φ = 59941512.

The previous prime is 61606547. The next prime is 61606631. The reversal of 61606591 is 19560616.

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 61606591 - 2¹⁹ = 61082303 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61606541) 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, 832485 + ... + 832558.

It is an arithmetic number, because the mean of its divisors is an integer number (15817918).

Almost surely, 2^61606591 is an apocalyptic number.

61606591 is a deficient number, since it is larger than the sum of its proper divisors (1665081).

61606591 is a wasteful number, since it uses less digits than its factorization.

61606591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1665080.

The product of its (nonzero) digits is 9720, while the sum is 34.

The square root of 61606591 is about 7848.9866224883. The cubic root of 61606591 is about 394.9502495692.

The spelling of 61606591 in words is "sixty-one million, six hundred six thousand, five hundred ninety-one".