120511721 has 4 divisors (see below), whose sum is σ = 131467344. Its totient is φ = 109556100.

The previous prime is 120511711. The next prime is 120511739. The reversal of 120511721 is 127115021.

It is a happy number.

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: 127115021 = 11 ⋅11555911.

It is a cyclic number.

It is not a de Polignac number, because 120511721 - 2¹⁰ = 120510697 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 120511693 and 120511702.

It is not an unprimeable number, because it can be changed into a prime (120511711) 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 3 ways as a sum of consecutive naturals, for example, 5477795 + ... + 5477816.

It is an arithmetic number, because the mean of its divisors is an integer number (32866836).

Almost surely, 2^120511721 is an apocalyptic number.

120511721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

120511721 is a deficient number, since it is larger than the sum of its proper divisors (10955623).

120511721 is a wasteful number, since it uses less digits than its factorization.

120511721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10955622.

The product of its (nonzero) digits is 140, while the sum is 20.

The square root of 120511721 is about 10977.7830639888. The cubic root of 120511721 is about 493.9425386786.

Adding to 120511721 its reverse (127115021), we get a palindrome (247626742).

The spelling of 120511721 in words is "one hundred twenty million, five hundred eleven thousand, seven hundred twenty-one".