138977280 has 336 divisors, whose sum is σ = 536707080. Its totient is φ = 33030144.

The previous prime is 138977269. The next prime is 138977281. The reversal of 138977280 is 82779831.

It can be written as a sum of positive squares in 4 ways, for example, as 88510464 + 50466816 = 9408^2 + 7104^2 .

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

It is not an unprimeable number, because it can be changed into a prime (138977281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4792306 + ... + 4792334.

Almost surely, 2^138977280 is an apocalyptic number.

138977280 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 138977280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (268353540).

138977280 is an abundant number, since it is smaller than the sum of its proper divisors (397729800).

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

138977280 is a wasteful number, since it uses less digits than its factorization.

138977280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79 (or 52 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 45.

The square root of 138977280 is about 11788.8625405507. The cubic root of 138977280 is about 517.9819217217.

The spelling of 138977280 in words is "one hundred thirty-eight million, nine hundred seventy-seven thousand, two hundred eighty".