139405390 has 8 divisors (see below), whose sum is σ = 250929720. Its totient is φ = 55762152.

The previous prime is 139405373. The next prime is 139405397. The reversal of 139405390 is 93504931.

139405390 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is a super-2 number, since 2×139405390² = 38867725522104200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139405397) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6970260 + ... + 6970279.

It is an arithmetic number, because the mean of its divisors is an integer number (31366215).

Almost surely, 2^139405390 is an apocalyptic number.

139405390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

139405390 is a deficient number, since it is larger than the sum of its proper divisors (111524330).

139405390 is a wasteful number, since it uses less digits than its factorization.

139405390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13940546.

The product of its (nonzero) digits is 14580, while the sum is 34.

The square root of 139405390 is about 11807.0059710326. The cubic root of 139405390 is about 518.5132458125.

The spelling of 139405390 in words is "one hundred thirty-nine million, four hundred five thousand, three hundred ninety".