509435987246621 has 4 divisors (see below), whose sum is σ = 539402810025852. Its totient is φ = 479469164467392.

The previous prime is 509435987246591. The next prime is 509435987246743. The reversal of 509435987246621 is 126642789534905.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 363695221932025 + 145740765314596 = 19070795^2 + 12072314^2 .

It is a cyclic number.

It is not a de Polignac number, because 509435987246621 - 2²² = 509435983052317 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 (509435987242621) 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, 14983411389590 + ... + 14983411389623.

It is an arithmetic number, because the mean of its divisors is an integer number (134850702506463).

It is a 1-persistent number, because it is pandigital, but 2⋅509435987246621 = 1018871974493242 is not.

Almost surely, 2^{509435987246621} is an apocalyptic number.

It is an amenable number.

509435987246621 is a deficient number, since it is larger than the sum of its proper divisors (29966822779231).

509435987246621 is a wasteful number, since it uses less digits than its factorization.

509435987246621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29966822779230.

The product of its (nonzero) digits is 783820800, while the sum is 71.

The spelling of 509435987246621 in words is "five hundred nine trillion, four hundred thirty-five billion, nine hundred eighty-seven million, two hundred forty-six thousand, six hundred twenty-one".