1538997408 has 120 divisors (see below), whose sum is σ = 4874420628. Its totient is φ = 473527296.

The previous prime is 1538997401. The next prime is 1538997503. The reversal of 1538997408 is 8047998351.

1538997408 is a `hidden beast` number, since 153 + 89 + 9 + 7 + 408 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1531313424 + 7683984 = 39132^2 + 2772^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (1538997401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 10860 + ... + 56532.

Almost surely, 2^1538997408 is an apocalyptic number.

1538997408 is a gapful number since it is divisible by the number (18) 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 1538997408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2437210314).

1538997408 is an abundant number, since it is smaller than the sum of its proper divisors (3335423220).

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

1538997408 is a wasteful number, since it uses less digits than its factorization.

1538997408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45708 (or 45691 counting only the distinct ones).

The product of its (nonzero) digits is 2177280, while the sum is 54.

The square root of 1538997408 is about 39230.0574559865. The cubic root of 1538997408 is about 1154.5496912141.

The spelling of 1538997408 in words is "one billion, five hundred thirty-eight million, nine hundred ninety-seven thousand, four hundred eight".