61335661 has 4 divisors (see below), whose sum is σ = 61726492. Its totient is φ = 60944832.

The previous prime is 61335653. The next prime is 61335671. The reversal of 61335661 is 16653316.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 35640900 + 25694761 = 5970^2 + 5069^2 .

It is a cyclic number.

It is not a de Polignac number, because 61335661 - 2³ = 61335653 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 (61335601) 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, 195180 + ... + 195493.

It is an arithmetic number, because the mean of its divisors is an integer number (15431623).

Almost surely, 2^61335661 is an apocalyptic number.

It is an amenable number.

61335661 is a deficient number, since it is larger than the sum of its proper divisors (390831).

61335661 is a wasteful number, since it uses less digits than its factorization.

61335661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390830.

The product of its digits is 9720, while the sum is 31.

The square root of 61335661 is about 7831.7086896794. The cubic root of 61335661 is about 394.3704354494.

Adding to 61335661 its reverse (16653316), we get a palindrome (77988977).

The spelling of 61335661 in words is "sixty-one million, three hundred thirty-five thousand, six hundred sixty-one".