139278493 has 12 divisors (see below), whose sum is σ = 147625308. Its totient is φ = 131382720.

The previous prime is 139278463. The next prime is 139278497. The reversal of 139278493 is 394872931.

It can be written as a sum of positive squares in 2 ways, for example, as 122279364 + 16999129 = 11058^2 + 4123^2 .

It is not a de Polignac number, because 139278493 - 2¹³ = 139270301 is a prime.

It is a super-2 number, since 2×139278493² = 38796997224702098, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139278497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 100755 + ... + 102127.

It is an arithmetic number, because the mean of its divisors is an integer number (12302109).

Almost surely, 2^139278493 is an apocalyptic number.

It is an amenable number.

139278493 is a deficient number, since it is larger than the sum of its proper divisors (8346815).

139278493 is a wasteful number, since it uses less digits than its factorization.

139278493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1692 (or 1673 counting only the distinct ones).

The product of its digits is 326592, while the sum is 46.

The square root of 139278493 is about 11801.6309466107. The cubic root of 139278493 is about 518.3558684683.

The spelling of 139278493 in words is "one hundred thirty-nine million, two hundred seventy-eight thousand, four hundred ninety-three".