21144144402 has 24 divisors (see below), whose sum is σ = 46173044736. Its totient is φ = 6992550936.

The previous prime is 21144144397. The next prime is 21144144479. The reversal of 21144144402 is 20444144112.

It is a happy number.

21144144402 is a `hidden beast` number, since 2 + 114 + 4 + 144 + 402 = 666.

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 11 ways as a sum of consecutive naturals, for example, 4622418 + ... + 4626989.

It is an arithmetic number, because the mean of its divisors is an integer number (1923876864).

Almost surely, 2^21144144402 is an apocalyptic number.

21144144402 is an abundant number, since it is smaller than the sum of its proper divisors (25028900334).

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

21144144402 is a wasteful number, since it uses less digits than its factorization.

21144144402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9249542 (or 9249539 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 27.

Adding to 21144144402 its reverse (20444144112), we get a palindrome (41588288514).

The spelling of 21144144402 in words is "twenty-one billion, one hundred forty-four million, one hundred forty-four thousand, four hundred two".