513551432261 has 4 divisors (see below), whose sum is σ = 586915922592. Its totient is φ = 440186941932.

The previous prime is 513551432221. The next prime is 513551432263. The reversal of 513551432261 is 162234155315.

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: 162234155315 = 5 ⋅32446831063.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-513551432261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (513551432263) 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, 36682245155 + ... + 36682245168.

It is an arithmetic number, because the mean of its divisors is an integer number (146728980648).

Almost surely, 2^513551432261 is an apocalyptic number.

It is an amenable number.

513551432261 is a deficient number, since it is larger than the sum of its proper divisors (73364490331).

513551432261 is an equidigital number, since it uses as much as digits as its factorization.

513551432261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73364490330.

The product of its digits is 108000, while the sum is 38.

Adding to 513551432261 its reverse (162234155315), we get a palindrome (675785587576).

The spelling of 513551432261 in words is "five hundred thirteen billion, five hundred fifty-one million, four hundred thirty-two thousand, two hundred sixty-one".