61720823 has 8 divisors (see below), whose sum is σ = 63307200. Its totient is φ = 60145920.

The previous prime is 61720801. The next prime is 61720849. The reversal of 61720823 is 32802716.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 61720823 - 2¹⁰ = 61719799 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61720423) 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 7 ways as a sum of consecutive naturals, for example, 8603 + ... + 14051.

It is an arithmetic number, because the mean of its divisors is an integer number (7913400).

Almost surely, 2^61720823 is an apocalyptic number.

61720823 is a deficient number, since it is larger than the sum of its proper divisors (1586377).

61720823 is a wasteful number, since it uses less digits than its factorization.

61720823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5737.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 61720823 is about 7856.2601153475. The cubic root of 61720823 is about 395.1942066954.

The spelling of 61720823 in words is "sixty-one million, seven hundred twenty thousand, eight hundred twenty-three".