138280749 has 8 divisors (see below), whose sum is σ = 185248992. Its totient is φ = 91749840.

The previous prime is 138280691. The next prime is 138280781. The reversal of 138280749 is 947082831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 138280749 - 2⁷ = 138280621 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138280749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138280799) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 108594 + ... + 109859.

It is an arithmetic number, because the mean of its divisors is an integer number (23156124).

Almost surely, 2^138280749 is an apocalyptic number.

It is an amenable number.

138280749 is a deficient number, since it is larger than the sum of its proper divisors (46968243).

138280749 is a wasteful number, since it uses less digits than its factorization.

138280749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218667.

The product of its (nonzero) digits is 96768, while the sum is 42.

The square root of 138280749 is about 11759.2835240928. The cubic root of 138280749 is about 517.1151256276.

The spelling of 138280749 in words is "one hundred thirty-eight million, two hundred eighty thousand, seven hundred forty-nine".