138401930 has 16 divisors (see below), whose sum is σ = 263778120. Its totient is φ = 52104192.

The previous prime is 138401927. The next prime is 138401951. The reversal of 138401930 is 39104831.

138401930 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 131171209 + 7230721 = 11453^2 + 2689^2 .

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 138401893 and 138401902.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 406895 + ... + 407234.

Almost surely, 2^138401930 is an apocalyptic number.

138401930 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

138401930 is a deficient number, since it is larger than the sum of its proper divisors (125376190).

138401930 is a wasteful number, since it uses less digits than its factorization.

138401930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 814153.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 138401930 is about 11764.4349630571. The cubic root of 138401930 is about 517.2661378070.

The spelling of 138401930 in words is "one hundred thirty-eight million, four hundred one thousand, nine hundred thirty".