21144155452 has 12 divisors (see below), whose sum is σ = 42288310960. Its totient is φ = 9061780896.

The previous prime is 21144155447. The next prime is 21144155479. The reversal of 21144155452 is 25455144112.

21144155452 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 377574177 + ... + 377574232.

Almost surely, 2^21144155452 is an apocalyptic number.

It is an amenable number.

21144155452 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21144155452 is a wasteful number, since it uses less digits than its factorization.

21144155452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 755148420 (or 755148418 counting only the distinct ones).

The product of its digits is 32000, while the sum is 34.

Adding to 21144155452 its reverse (25455144112), we get a palindrome (46599299564).

The spelling of 21144155452 in words is "twenty-one billion, one hundred forty-four million, one hundred fifty-five thousand, four hundred fifty-two".