21140400042 has 12 divisors (see below), whose sum is σ = 45804200130. Its totient is φ = 7046800008.

The previous prime is 21140400037. The next prime is 21140400097. The reversal of 21140400042 is 24000404112.

It can be written as a sum of positive squares in only one way, i.e., 21054300201 + 86099841 = 145101^2 + 9279^2 .

It is a Harshad number since it is a multiple of its sum of digits (18), and also a Moran number because the ratio is a prime number: 1174466669 = 21140400042 / (2 + 1 + 1 + 4 + 0 + 4 + 0 + 0 + 0 + 4 + 2).

It is a junction number, because it is equal to n+sod(n) for n = 21140399988 and 21140400024.

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 5 ways as a sum of consecutive naturals, for example, 587233317 + ... + 587233352.

Almost surely, 2^21140400042 is an apocalyptic number.

21140400042 is an abundant number, since it is smaller than the sum of its proper divisors (24663800088).

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

21140400042 is a wasteful number, since it uses less digits than its factorization.

21140400042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1174466677 (or 1174466674 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 21140400042 its reverse (24000404112), we get a palindrome (45140804154).

The spelling of 21140400042 in words is "twenty-one billion, one hundred forty million, four hundred thousand, forty-two".