1378888665 has 96 divisors (see below), whose sum is σ = 2896767360. Its totient is φ = 553190400.

The previous prime is 1378888661. The next prime is 1378888669. The reversal of 1378888665 is 5668888731.

It is an interprime number because it is at equal distance from previous prime (1378888661) and next prime (1378888669).

It is not a de Polignac number, because 1378888665 - 2² = 1378888661 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1378888599 and 1378888608.

It is not an unprimeable number, because it can be changed into a prime (1378888661) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 231525 + ... + 237405.

It is an arithmetic number, because the mean of its divisors is an integer number (30174660).

Almost surely, 2^1378888665 is an apocalyptic number.

1378888665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1378888665 is an abundant number, since it is smaller than the sum of its proper divisors (1517878695).

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

1378888665 is a wasteful number, since it uses less digits than its factorization.

1378888665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5943 (or 5936 counting only the distinct ones).

The product of its digits is 15482880, while the sum is 60.

The square root of 1378888665 is about 37133.3901630325. The cubic root of 1378888665 is about 1113.0373390424.

The spelling of 1378888665 in words is "one billion, three hundred seventy-eight million, eight hundred eighty-eight thousand, six hundred sixty-five".