61223813 has 4 divisors (see below), whose sum is σ = 69970080. Its totient is φ = 52477548.

The previous prime is 61223777. The next prime is 61223819. The reversal of 61223813 is 31832216.

61223813 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 61223813 - 2⁸ = 61223557 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61223819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4373123 + ... + 4373136.

It is an arithmetic number, because the mean of its divisors is an integer number (17492520).

Almost surely, 2^61223813 is an apocalyptic number.

It is an amenable number.

61223813 is a deficient number, since it is larger than the sum of its proper divisors (8746267).

61223813 is an equidigital number, since it uses as much as digits as its factorization.

61223813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8746266.

The product of its digits is 1728, while the sum is 26.

The square root of 61223813 is about 7824.5647163277. The cubic root of 61223813 is about 394.1305729030.

The spelling of 61223813 in words is "sixty-one million, two hundred twenty-three thousand, eight hundred thirteen".