61771609 has 4 divisors (see below), whose sum is σ = 62243280. Its totient is φ = 61299940.

The previous prime is 61771597. The next prime is 61771627. The reversal of 61771609 is 90617716.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 61771609 - 2⁷ = 61771481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61771639) 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, 235639 + ... + 235900.

It is an arithmetic number, because the mean of its divisors is an integer number (15560820).

Almost surely, 2^61771609 is an apocalyptic number.

It is an amenable number.

61771609 is a deficient number, since it is larger than the sum of its proper divisors (471671).

61771609 is a wasteful number, since it uses less digits than its factorization.

61771609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471670.

The product of its (nonzero) digits is 15876, while the sum is 37.

The square root of 61771609 is about 7859.4916502278. The cubic root of 61771609 is about 395.3025700735.

The spelling of 61771609 in words is "sixty-one million, seven hundred seventy-one thousand, six hundred nine".