138477966 has 48 divisors (see below), whose sum is σ = 320476800. Its totient is φ = 39750480.

The previous prime is 138477959. The next prime is 138478003. The reversal of 138477966 is 669774831.

It is a super-2 number, since 2×138477966² = 38352294134994312, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8775 + ... + 18813.

It is an arithmetic number, because the mean of its divisors is an integer number (6676600).

Almost surely, 2^138477966 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138477966, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (160238400).

138477966 is an abundant number, since it is smaller than the sum of its proper divisors (181998834).

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

138477966 is a wasteful number, since it uses less digits than its factorization.

138477966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10085 (or 10074 counting only the distinct ones).

The product of its digits is 1524096, while the sum is 51.

The square root of 138477966 is about 11767.6661237477. Note that the first 3 decimals coincide. The cubic root of 138477966 is about 517.3608466203.

The spelling of 138477966 in words is "one hundred thirty-eight million, four hundred seventy-seven thousand, nine hundred sixty-six".