21004342045 has 16 divisors (see below), whose sum is σ = 25268040000. Its totient is φ = 16761644928.

The previous prime is 21004342043. The next prime is 21004342069. The reversal of 21004342045 is 54024340012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21004342045 - 2¹ = 21004342043 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21004342043) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3873346 + ... + 3878764.

It is an arithmetic number, because the mean of its divisors is an integer number (1579252500).

Almost surely, 2^21004342045 is an apocalyptic number.

It is an amenable number.

21004342045 is a deficient number, since it is larger than the sum of its proper divisors (4263697955).

21004342045 is a wasteful number, since it uses less digits than its factorization.

21004342045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7212.

The product of its (nonzero) digits is 3840, while the sum is 25.

Adding to 21004342045 its reverse (54024340012), we get a palindrome (75028682057).

The spelling of 21004342045 in words is "twenty-one billion, four million, three hundred forty-two thousand, forty-five".