61216809 has 8 divisors (see below), whose sum is σ = 81661440. Its totient is φ = 40791696.

The previous prime is 61216787. The next prime is 61216811. The reversal of 61216809 is 90861216.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61216809 - 2⁷ = 61216681 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61216809.

It is not an unprimeable number, because it can be changed into a prime (61215809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5752 + ... + 12470.

It is an arithmetic number, because the mean of its divisors is an integer number (10207680).

Almost surely, 2^61216809 is an apocalyptic number.

It is an amenable number.

61216809 is a deficient number, since it is larger than the sum of its proper divisors (20444631).

61216809 is a wasteful number, since it uses less digits than its factorization.

61216809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9759.

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 61216809 is about 7824.1171386937. The cubic root of 61216809 is about 394.1155428264.

The spelling of 61216809 in words is "sixty-one million, two hundred sixteen thousand, eight hundred nine".