2155138395648 has 640 divisors, whose sum is σ = 7166462459904. Its totient is φ = 562028544000.

The previous prime is 2155138395623. The next prime is 2155138395649. The reversal of 2155138395648 is 8465938315512.

It is a junction number, because it is equal to n+sod(n) for n = 2155138395591 and 2155138395600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2155138395649) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 559628923 + ... + 559632773.

Almost surely, 2^{2155138395648} is an apocalyptic number.

2155138395648 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2155138395648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3583231229952).

2155138395648 is an abundant number, since it is smaller than the sum of its proper divisors (5011324064256).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2155138395648 is a wasteful number, since it uses less digits than its factorization.

2155138395648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4006 (or 3990 counting only the distinct ones).

The product of its digits is 31104000, while the sum is 60.

The spelling of 2155138395648 in words is "two trillion, one hundred fifty-five billion, one hundred thirty-eight million, three hundred ninety-five thousand, six hundred forty-eight".