61653665 has 4 divisors (see below), whose sum is σ = 73984404. Its totient is φ = 49322928.

The previous prime is 61653653. The next prime is 61653671. The reversal of 61653665 is 56635616.

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 46730896 + 14922769 = 6836^2 + 3863^2 .

It is a cyclic number.

It is not a de Polignac number, because 61653665 - 2¹⁰ = 61652641 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6165362 + ... + 6165371.

It is an arithmetic number, because the mean of its divisors is an integer number (18496101).

Almost surely, 2^61653665 is an apocalyptic number.

It is an amenable number.

61653665 is a deficient number, since it is larger than the sum of its proper divisors (12330739).

61653665 is a wasteful number, since it uses less digits than its factorization.

61653665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12330738.

The product of its digits is 97200, while the sum is 38.

The square root of 61653665 is about 7851.9847809328. The cubic root of 61653665 is about 395.0508186499.

The spelling of 61653665 in words is "sixty-one million, six hundred fifty-three thousand, six hundred sixty-five".