15640135123 has 4 divisors (see below), whose sum is σ = 15794988048. Its totient is φ = 15485282200.

The previous prime is 15640135073. The next prime is 15640135141. The reversal of 15640135123 is 32153104651.

15640135123 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32153104651 = 673 ⋅47775787.

It is a cyclic number.

It is not a de Polignac number, because 15640135123 - 2²¹ = 15638037971 is a prime.

It is a super-2 number, since 2×15640135123² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (15640135523) 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, 77426311 + ... + 77426512.

It is an arithmetic number, because the mean of its divisors is an integer number (3948747012).

Almost surely, 2^15640135123 is an apocalyptic number.

15640135123 is a deficient number, since it is larger than the sum of its proper divisors (154852925).

15640135123 is a wasteful number, since it uses less digits than its factorization.

15640135123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154852924.

The product of its (nonzero) digits is 10800, while the sum is 31.

Adding to 15640135123 its reverse (32153104651), we get a palindrome (47793239774).

The spelling of 15640135123 in words is "fifteen billion, six hundred forty million, one hundred thirty-five thousand, one hundred twenty-three".