139405428 has 24 divisors (see below), whose sum is σ = 361421760. Its totient is φ = 46468440.

The previous prime is 139405411. The next prime is 139405433. The reversal of 139405428 is 824504931.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 139405392 and 139405401.

It is a congruent number.

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, 645288 + ... + 645503.

It is an arithmetic number, because the mean of its divisors is an integer number (15059240).

Almost surely, 2^139405428 is an apocalyptic number.

139405428 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

139405428 is an abundant number, since it is smaller than the sum of its proper divisors (222016332).

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

139405428 is a wasteful number, since it uses less digits than its factorization.

139405428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1290804 (or 1290796 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 139405428 is about 11807.0075802466. The cubic root of 139405428 is about 518.5132929257.

The spelling of 139405428 in words is "one hundred thirty-nine million, four hundred five thousand, four hundred twenty-eight".