13780028655 has 24 divisors (see below), whose sum is σ = 24017360640. Its totient is φ = 7308740160.

The previous prime is 13780028651. The next prime is 13780028699. The reversal of 13780028655 is 55682008731.

It is not a de Polignac number, because 13780028655 - 2² = 13780028651 is a prime.

It is a super-2 number, since 2×13780028655² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 13780028655.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13780028651) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 837775 + ... + 854064.

It is an arithmetic number, because the mean of its divisors is an integer number (1000723360).

Almost surely, 2^13780028655 is an apocalyptic number.

13780028655 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

13780028655 is a deficient number, since it is larger than the sum of its proper divisors (10237331985).

13780028655 is a wasteful number, since it uses less digits than its factorization.

13780028655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1692031 (or 1692028 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 45.

The spelling of 13780028655 in words is "thirteen billion, seven hundred eighty million, twenty-eight thousand, six hundred fifty-five".