130511721 has 4 divisors (see below), whose sum is σ = 174015632. Its totient is φ = 87007812.

The previous prime is 130511707. The next prime is 130511747. The reversal of 130511721 is 127115031.

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.

It is not a de Polignac number, because 130511721 - 2⁷ = 130511593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (130511761) 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, 21751951 + ... + 21751956.

It is an arithmetic number, because the mean of its divisors is an integer number (43503908).

Almost surely, 2^130511721 is an apocalyptic number.

It is an amenable number.

130511721 is a deficient number, since it is larger than the sum of its proper divisors (43503911).

130511721 is an equidigital number, since it uses as much as digits as its factorization.

130511721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43503910.

The product of its (nonzero) digits is 210, while the sum is 21.

The square root of 130511721 is about 11424.1726615103. The cubic root of 130511721 is about 507.2435174994.

Adding to 130511721 its reverse (127115031), we get a palindrome (257626752).

The spelling of 130511721 in words is "one hundred thirty million, five hundred eleven thousand, seven hundred twenty-one".