138470640 has 320 divisors, whose sum is σ = 548536320. Its totient is φ = 28062720.

The previous prime is 138470639. The next prime is 138470659. The reversal of 138470640 is 46074831.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1090257 + ... + 1090383.

It is an arithmetic number, because the mean of its divisors is an integer number (1714176).

Almost surely, 2^138470640 is an apocalyptic number.

138470640 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 138470640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (274268160).

138470640 is an abundant number, since it is smaller than the sum of its proper divisors (410065680).

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

138470640 is a wasteful number, since it uses less digits than its factorization.

138470640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220 (or 214 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 33.

The square root of 138470640 is about 11767.3548429543. The cubic root of 138470640 is about 517.3517230210.

The spelling of 138470640 in words is "one hundred thirty-eight million, four hundred seventy thousand, six hundred forty".