1398178440 has 48 divisors (see below), whose sum is σ = 4544081100. Its totient is φ = 372847488.

The previous prime is 1398178429. The next prime is 1398178471. The reversal of 1398178440 is 448718931.

It is a happy number.

1398178440 is a `hidden beast` number, since 1 + 39 + 8 + 178 + 440 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1125334116 + 272844324 = 33546^2 + 16518^2 .

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

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, 1941555 + ... + 1942274.

Almost surely, 2^1398178440 is an apocalyptic number.

1398178440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1398178440 is an abundant number, since it is smaller than the sum of its proper divisors (3145902660).

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

1398178440 is a wasteful number, since it uses less digits than its factorization.

1398178440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3883846 (or 3883839 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 1398178440 is about 37392.2243253862. The cubic root of 1398178440 is about 1118.2035507827.

The spelling of 1398178440 in words is "one billion, three hundred ninety-eight million, one hundred seventy-eight thousand, four hundred forty".