21001240502132 has 18 divisors (see below), whose sum is σ = 40397014272594. Its totient is φ = 9546018409840.

The previous prime is 21001240502111. The next prime is 21001240502149. The reversal of 21001240502132 is 23120504210012.

It can be written as a sum of positive squares in only one way, i.e., 20513706990436 + 487533511696 = 4529206^2 + 698236^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21001240502098 and 21001240502107.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 21695495903 + ... + 21695496870.

Almost surely, 2^{21001240502132} is an apocalyptic number.

21001240502132 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21001240502132 is a deficient number, since it is larger than the sum of its proper divisors (19395773770462).

21001240502132 is a wasteful number, since it uses less digits than its factorization.

21001240502132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43390992799 (or 43390992786 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 21001240502132 its reverse (23120504210012), we get a palindrome (44121744712144).

The spelling of 21001240502132 in words is "twenty-one trillion, one billion, two hundred forty million, five hundred two thousand, one hundred thirty-two".