513128749 has 4 divisors (see below), whose sum is σ = 586432864. Its totient is φ = 439824636.

The previous prime is 513128747. The next prime is 513128797. The reversal of 513128749 is 947821315.

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 513128749 - 2¹ = 513128747 is a prime.

It is a super-2 number, since 2×513128749² = 526602226100610002, 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 (513128741) 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, 36652047 + ... + 36652060.

It is an arithmetic number, because the mean of its divisors is an integer number (146608216).

Almost surely, 2^513128749 is an apocalyptic number.

It is an amenable number.

513128749 is a deficient number, since it is larger than the sum of its proper divisors (73304115).

513128749 is an equidigital number, since it uses as much as digits as its factorization.

513128749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73304114.

The product of its digits is 60480, while the sum is 40.

The square root of 513128749 is about 22652.3453311131. The cubic root of 513128749 is about 800.5874586140.

The spelling of 513128749 in words is "five hundred thirteen million, one hundred twenty-eight thousand, seven hundred forty-nine".