138799620 has 36 divisors (see below), whose sum is σ = 421026060. Its totient is φ = 37013184.

The previous prime is 138799559. The next prime is 138799621. The reversal of 138799620 is 26997831.

138799620 is a `hidden beast` number, since 13 + 8 + 7 + 9 + 9 + 620 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 109118916 + 29680704 = 10446^2 + 5448^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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 (138799621) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 385375 + ... + 385734.

Almost surely, 2^138799620 is an apocalyptic number.

138799620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138799620 is an abundant number, since it is smaller than the sum of its proper divisors (282226440).

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

138799620 is a wasteful number, since it uses less digits than its factorization.

138799620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 771124 (or 771119 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The square root of 138799620 is about 11781.3250528113. The cubic root of 138799620 is about 517.7611088689.

The spelling of 138799620 in words is "one hundred thirty-eight million, seven hundred ninety-nine thousand, six hundred twenty".