21144340057 has 8 divisors (see below), whose sum is σ = 22262038560. Its totient is φ = 20027125440.

The previous prime is 21144340043. The next prime is 21144340069. The reversal of 21144340057 is 75004344112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21144340057 - 2⁷ = 21144339929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21144340157) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29488 + ... + 207745.

It is an arithmetic number, because the mean of its divisors is an integer number (2782754820).

Almost surely, 2^21144340057 is an apocalyptic number.

It is an amenable number.

21144340057 is a deficient number, since it is larger than the sum of its proper divisors (1117698503).

21144340057 is a wasteful number, since it uses less digits than its factorization.

21144340057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241943.

The product of its (nonzero) digits is 13440, while the sum is 31.

Adding to 21144340057 its reverse (75004344112), we get a palindrome (96148684169).

It can be divided in two parts, 21144 and 340057, that added together give a square (361201 = 601²).

The spelling of 21144340057 in words is "twenty-one billion, one hundred forty-four million, three hundred forty thousand, fifty-seven".