61509611 has 4 divisors (see below), whose sum is σ = 63493824. Its totient is φ = 59525400.

The previous prime is 61509601. The next prime is 61509641. The reversal of 61509611 is 11690516.

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 61509611 - 2¹⁴ = 61493227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61509601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 992060 + ... + 992121.

It is an arithmetic number, because the mean of its divisors is an integer number (15873456).

Almost surely, 2^61509611 is an apocalyptic number.

61509611 is a deficient number, since it is larger than the sum of its proper divisors (1984213).

61509611 is a wasteful number, since it uses less digits than its factorization.

61509611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1984212.

The product of its (nonzero) digits is 1620, while the sum is 29.

The square root of 61509611 is about 7842.8063217193. The cubic root of 61509611 is about 394.7428995091.

The spelling of 61509611 in words is "sixty-one million, five hundred nine thousand, six hundred eleven".