12540345405 has 32 divisors (see below), whose sum is σ = 22959417600. Its totient is φ = 5725604352.

The previous prime is 12540345397. The next prime is 12540345427. The reversal of 12540345405 is 50454304521.

It is not a de Polignac number, because 12540345405 - 2³ = 12540345397 is a prime.

It is a super-2 number, since 2×12540345405² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11131 + ... + 158759.

It is an arithmetic number, because the mean of its divisors is an integer number (717481800).

Almost surely, 2^12540345405 is an apocalyptic number.

12540345405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12540345405 is a deficient number, since it is larger than the sum of its proper divisors (10419072195).

12540345405 is a wasteful number, since it uses less digits than its factorization.

12540345405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148453.

The product of its (nonzero) digits is 48000, while the sum is 33.

Adding to 12540345405 its reverse (50454304521), we get a palindrome (62994649926).

The spelling of 12540345405 in words is "twelve billion, five hundred forty million, three hundred forty-five thousand, four hundred five".