139218525 has 54 divisors (see below), whose sum is σ = 265010382. Its totient is φ = 69849600.

The previous prime is 139218511. The next prime is 139218539. The reversal of 139218525 is 525812931.

It is an interprime number because it is at equal distance from previous prime (139218511) and next prime (139218539).

It can be written as a sum of positive squares in 9 ways, for example, as 285156 + 138933369 = 534^2 + 11787^2 .

It is not a de Polignac number, because 139218525 - 2¹² = 139214429 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 139218525.

It is a congruent number.

It is an unprimeable number.

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 53 ways as a sum of consecutive naturals, for example, 63955 + ... + 66095.

Almost surely, 2^139218525 is an apocalyptic number.

139218525 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

139218525 is a deficient number, since it is larger than the sum of its proper divisors (125791857).

139218525 is a wasteful number, since it uses less digits than its factorization.

139218525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2191 (or 2166 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 139218525 is about 11799.0900072845. The cubic root of 139218525 is about 518.2814630417.

The spelling of 139218525 in words is "one hundred thirty-nine million, two hundred eighteen thousand, five hundred twenty-five".