21040442001 has 12 divisors (see below), whose sum is σ = 30393152400. Its totient is φ = 14026313880.

The previous prime is 21040441997. The next prime is 21040442039. The reversal of 21040442001 is 10024404012.

It is not a de Polignac number, because 21040442001 - 2² = 21040441997 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21040442041) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 231150 + ... + 309048.

It is an arithmetic number, because the mean of its divisors is an integer number (2532762700).

Almost surely, 2^21040442001 is an apocalyptic number.

It is an amenable number.

21040442001 is a deficient number, since it is larger than the sum of its proper divisors (9352710399).

21040442001 is a wasteful number, since it uses less digits than its factorization.

21040442001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107916 (or 107913 counting only the distinct ones).

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

Adding to 21040442001 its reverse (10024404012), we get a palindrome (31064846013).

It can be divided in two parts, 210404 and 42001, that added together give a triangular number (252405 = T₇₁₀).

The spelling of 21040442001 in words is "twenty-one billion, forty million, four hundred forty-two thousand, one".