21642311004 has 24 divisors (see below), whose sum is σ = 51730403088. Its totient is φ = 7038149760.

The previous prime is 21642311003. The next prime is 21642311063. The reversal of 21642311004 is 40011324612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21642311003) 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, 21993727 + ... + 21994710.

It is an arithmetic number, because the mean of its divisors is an integer number (2155433462).

Almost surely, 2^21642311004 is an apocalyptic number.

It is an amenable number.

21642311004 is an abundant number, since it is smaller than the sum of its proper divisors (30088092084).

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

21642311004 is a wasteful number, since it uses less digits than its factorization.

21642311004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43988485 (or 43988483 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

Adding to 21642311004 its reverse (40011324612), we get a palindrome (61653635616).

The spelling of 21642311004 in words is "twenty-one billion, six hundred forty-two million, three hundred eleven thousand, four".