138942744 has 64 divisors (see below), whose sum is σ = 377472000. Its totient is φ = 42456960.

The previous prime is 138942743. The next prime is 138942767. The reversal of 138942744 is 447249831.

It is a super-2 number, since 2×138942744² = 38610172220499072, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 138942696 and 138942705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138942743) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9222 + ... + 19050.

It is an arithmetic number, because the mean of its divisors is an integer number (5898000).

Almost surely, 2^138942744 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138942744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (188736000).

138942744 is an abundant number, since it is smaller than the sum of its proper divisors (238529256).

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

138942744 is a wasteful number, since it uses less digits than its factorization.

138942744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9888 (or 9884 counting only the distinct ones).

The product of its digits is 193536, while the sum is 42.

The square root of 138942744 is about 11787.3976771805. The cubic root of 138942744 is about 517.9390118166.

The spelling of 138942744 in words is "one hundred thirty-eight million, nine hundred forty-two thousand, seven hundred forty-four".