21042131513 has 8 divisors (see below), whose sum is σ = 22677852288. Its totient is φ = 19408852944.

The previous prime is 21042131507. The next prime is 21042131543. The reversal of 21042131513 is 31513124012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21042131513 - 2¹⁰ = 21042130489 is a prime.

It is a super-2 number, since 2×21042131513² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21042131503) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 592631 + ... + 627132.

It is an arithmetic number, because the mean of its divisors is an integer number (2834731536).

Almost surely, 2^21042131513 is an apocalyptic number.

It is an amenable number.

21042131513 is a deficient number, since it is larger than the sum of its proper divisors (1635720775).

21042131513 is a wasteful number, since it uses less digits than its factorization.

21042131513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1221103.

The product of its (nonzero) digits is 720, while the sum is 23.

Adding to 21042131513 its reverse (31513124012), we get a palindrome (52555255525).

The spelling of 21042131513 in words is "twenty-one billion, forty-two million, one hundred thirty-one thousand, five hundred thirteen".