61289281 has 4 divisors (see below), whose sum is σ = 61308864. Its totient is φ = 61269700.

The previous prime is 61289243. The next prime is 61289287. The reversal of 61289281 is 18298216.

61289281 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 61289281 - 2⁹ = 61288769 is a prime.

It is a super-2 number, since 2×61289281² = 7512751930993922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 61289281.

It is not an unprimeable number, because it can be changed into a prime (61289287) 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, 3925 + ... + 11746.

It is an arithmetic number, because the mean of its divisors is an integer number (15327216).

Almost surely, 2^61289281 is an apocalyptic number.

It is an amenable number.

61289281 is a deficient number, since it is larger than the sum of its proper divisors (19583).

61289281 is a wasteful number, since it uses less digits than its factorization.

61289281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19582.

The product of its digits is 13824, while the sum is 37.

The square root of 61289281 is about 7828.7470900521. The cubic root of 61289281 is about 394.2710070866.

The spelling of 61289281 in words is "sixty-one million, two hundred eighty-nine thousand, two hundred eighty-one".