61281817 has 2 divisors, whose sum is σ = 61281818. Its totient is φ = 61281816.

The previous prime is 61281811. The next prime is 61281827. The reversal of 61281817 is 71818216.

61281817 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42653961 + 18627856 = 6531^2 + 4316^2 .

It is a cyclic number.

It is not a de Polignac number, because 61281817 - 2³ = 61281809 is a prime.

It is a super-2 number, since 2×61281817² = 7510922189642978, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (61281811) 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 as a sum of consecutive naturals, namely, 30640908 + 30640909.

It is an arithmetic number, because the mean of its divisors is an integer number (30640909).

Almost surely, 2^61281817 is an apocalyptic number.

It is an amenable number.

61281817 is a deficient number, since it is larger than the sum of its proper divisors (1).

61281817 is an equidigital number, since it uses as much as digits as its factorization.

61281817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5376, while the sum is 34.

The square root of 61281817 is about 7828.2703709057. The cubic root of 61281817 is about 394.2550012521.

The spelling of 61281817 in words is "sixty-one million, two hundred eighty-one thousand, eight hundred seventeen".