120509581 has 4 divisors (see below), whose sum is σ = 125749152. Its totient is φ = 115270012.

The previous prime is 120509569. The next prime is 120509593. The reversal of 120509581 is 185905021.

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, and also an emirpimes, since its reverse is a distinct semiprime: 185905021 = 23 ⋅8082827.

It is an interprime number because it is at equal distance from previous prime (120509569) and next prime (120509593).

It is a cyclic number.

It is not a de Polignac number, because 120509581 - 2¹⁹ = 119985293 is a prime.

It is a super-2 number, since 2×120509581² = 29045118225591122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (120500581) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2619751 + ... + 2619796.

It is an arithmetic number, because the mean of its divisors is an integer number (31437288).

Almost surely, 2^120509581 is an apocalyptic number.

It is an amenable number.

120509581 is a deficient number, since it is larger than the sum of its proper divisors (5239571).

120509581 is an equidigital number, since it uses as much as digits as its factorization.

120509581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5239570.

The product of its (nonzero) digits is 3600, while the sum is 31.

The square root of 120509581 is about 10977.6855939674. The cubic root of 120509581 is about 493.9396149152.

The spelling of 120509581 in words is "one hundred twenty million, five hundred nine thousand, five hundred eighty-one".