15438193440 has 192 divisors, whose sum is σ = 50384581632. Its totient is φ = 3969331200.

The previous prime is 15438193387. The next prime is 15438193483. The reversal of 15438193440 is 4439183451.

It is a junction number, because it is equal to n+sod(n) for n = 15438193392 and 15438193401.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4358070 + ... + 4361610.

It is an arithmetic number, because the mean of its divisors is an integer number (262419696).

Almost surely, 2^15438193440 is an apocalyptic number.

15438193440 is a gapful number since it is divisible by the number (10) 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 15438193440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25192290816).

15438193440 is an abundant number, since it is smaller than the sum of its proper divisors (34946388192).

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

15438193440 is a wasteful number, since it uses less digits than its factorization.

15438193440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3883 (or 3875 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 42.

The spelling of 15438193440 in words is "fifteen billion, four hundred thirty-eight million, one hundred ninety-three thousand, four hundred forty".