61356665 has 4 divisors (see below), whose sum is σ = 73628004. Its totient is φ = 49085328.

The previous prime is 61356661. The next prime is 61356677. The reversal of 61356665 is 56665316.

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 48832144 + 12524521 = 6988^2 + 3539^2 .

It is a cyclic number.

It is not a de Polignac number, because 61356665 - 2² = 61356661 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61356661) 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, 6135662 + ... + 6135671.

It is an arithmetic number, because the mean of its divisors is an integer number (18407001).

Almost surely, 2^61356665 is an apocalyptic number.

It is an amenable number.

61356665 is a deficient number, since it is larger than the sum of its proper divisors (12271339).

61356665 is a wasteful number, since it uses less digits than its factorization.

61356665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12271338.

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

The square root of 61356665 is about 7833.0495338661. The cubic root of 61356665 is about 394.4154468459.

The spelling of 61356665 in words is "sixty-one million, three hundred fifty-six thousand, six hundred sixty-five".