138651 has 8 divisors (see below), whose sum is σ = 186960. Its totient is φ = 91392.

The previous prime is 138647. The next prime is 138661. The reversal of 138651 is 156831.

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

It is not a de Polignac number, because 138651 - 2² = 138647 is a prime.

138651 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (138641) 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, 135 + ... + 543.

It is an arithmetic number, because the mean of its divisors is an integer number (23370).

2¹³⁸⁶⁵¹ is an apocalyptic number.

138651 is the 236-th centered pentagonal number.

138651 is a deficient number, since it is larger than the sum of its proper divisors (48309).

138651 is a wasteful number, since it uses less digits than its factorization.

138651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 525.

The product of its digits is 720, while the sum is 24.

The square root of 138651 is about 372.3586980319. The cubic root of 138651 is about 51.7576244921.

The spelling of 138651 in words is "one hundred thirty-eight thousand, six hundred fifty-one".