2155665406550 has 24 divisors (see below), whose sum is σ = 4011039041952. Its totient is φ = 861943284000.

The previous prime is 2155665406537. The next prime is 2155665406571. The reversal of 2155665406550 is 556045665512.

It is a Smith number, since the sum of its digits (50) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (50).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7937081 + ... + 8204180.

It is an arithmetic number, because the mean of its divisors is an integer number (167126626748).

Almost surely, 2^{2155665406550} is an apocalyptic number.

2155665406550 is a deficient number, since it is larger than the sum of its proper divisors (1855373635402).

2155665406550 is a wasteful number, since it uses less digits than its factorization.

2155665406550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16143944 (or 16143939 counting only the distinct ones).

The product of its (nonzero) digits is 5400000, while the sum is 50.

The spelling of 2155665406550 in words is "two trillion, one hundred fifty-five billion, six hundred sixty-five million, four hundred six thousand, five hundred fifty".