61667321 has 12 divisors (see below), whose sum is σ = 64246644. Its totient is φ = 59155200.

The previous prime is 61667317. The next prime is 61667323. The reversal of 61667321 is 12376616.

It can be written as a sum of positive squares in 2 ways, for example, as 21724921 + 39942400 = 4661^2 + 6320^2 .

It is not a de Polignac number, because 61667321 - 2² = 61667317 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61667323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 255761 + ... + 256001.

It is an arithmetic number, because the mean of its divisors is an integer number (5353887).

Almost surely, 2^61667321 is an apocalyptic number.

It is an amenable number.

61667321 is a deficient number, since it is larger than the sum of its proper divisors (2579323).

61667321 is an equidigital number, since it uses as much as digits as its factorization.

61667321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 440 (or 361 counting only the distinct ones).

The product of its digits is 9072, while the sum is 32.

The square root of 61667321 is about 7852.8543218374. The cubic root of 61667321 is about 395.0799838029.

The spelling of 61667321 in words is "sixty-one million, six hundred sixty-seven thousand, three hundred twenty-one".