138561000 has 64 divisors (see below), whose sum is σ = 432319680. Its totient is φ = 36948800.

The previous prime is 138560953. The next prime is 138561001. The reversal of 138561000 is 165831.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (138561001) 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, 20094 + ... + 26093.

It is an arithmetic number, because the mean of its divisors is an integer number (6754995).

Almost surely, 2^138561000 is an apocalyptic number.

138561000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138561000 is an abundant number, since it is smaller than the sum of its proper divisors (293758680).

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

138561000 is a wasteful number, since it uses less digits than its factorization.

138561000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46211 (or 46197 counting only the distinct ones).

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

The square root of 138561000 is about 11771.1936523022. The cubic root of 138561000 is about 517.4642323992.

The spelling of 138561000 in words is "one hundred thirty-eight million, five hundred sixty-one thousand".