139602021 has 16 divisors (see below), whose sum is σ = 206922240. Its totient is φ = 83136960.

The previous prime is 139602017. The next prime is 139602059. The reversal of 139602021 is 120206931.

It is not a de Polignac number, because 139602021 - 2² = 139602017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 139601982 and 139602000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139602721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56526 + ... + 58943.

It is an arithmetic number, because the mean of its divisors is an integer number (12932640).

Almost surely, 2^139602021 is an apocalyptic number.

It is an amenable number.

139602021 is a deficient number, since it is larger than the sum of its proper divisors (67320219).

139602021 is a wasteful number, since it uses less digits than its factorization.

139602021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115516.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 139602021 is about 11815.3299149876. The cubic root of 139602021 is about 518.7569185510.

Adding to 139602021 its reverse (120206931), we get a palindrome (259808952).

The spelling of 139602021 in words is "one hundred thirty-nine million, six hundred two thousand, twenty-one".