139440521 has 12 divisors (see below), whose sum is σ = 155437632. Its totient is φ = 124971000.

The previous prime is 139440479. The next prime is 139440527. The reversal of 139440521 is 125044931.

It is not a de Polignac number, because 139440521 - 2²² = 135246217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139440527) 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, 476 + ... + 16706.

It is an arithmetic number, because the mean of its divisors is an integer number (12953136).

Almost surely, 2^139440521 is an apocalyptic number.

139440521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

139440521 is a deficient number, since it is larger than the sum of its proper divisors (15997111).

139440521 is a wasteful number, since it uses less digits than its factorization.

139440521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16324 (or 16313 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 139440521 is about 11808.4935957132. The cubic root of 139440521 is about 518.5567983104.

The spelling of 139440521 in words is "one hundred thirty-nine million, four hundred forty thousand, five hundred twenty-one".