61665001 has 12 divisors (see below), whose sum is σ = 68264532. Its totient is φ = 55506176.

The previous prime is 61664959. The next prime is 61665007. The reversal of 61665001 is 10056616.

It can be written as a sum of positive squares in 2 ways, for example, as 18696976 + 42968025 = 4324^2 + 6555^2 .

It is not a de Polignac number, because 61665001 - 2⁷ = 61664873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61665007) 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 11 ways as a sum of consecutive naturals, for example, 5565 + ... + 12421.

It is an arithmetic number, because the mean of its divisors is an integer number (5688711).

Almost surely, 2^61665001 is an apocalyptic number.

It is an amenable number.

61665001 is a deficient number, since it is larger than the sum of its proper divisors (6599531).

61665001 is a wasteful number, since it uses less digits than its factorization.

61665001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6920 (or 6897 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 61665001 is about 7852.7066034585. The cubic root of 61665001 is about 395.0750292768.

The spelling of 61665001 in words is "sixty-one million, six hundred sixty-five thousand, one".