21031649804 has 48 divisors (see below), whose sum is σ = 40862495520. Its totient is φ = 9391964160.

The previous prime is 21031649801. The next prime is 21031649839. The reversal of 21031649804 is 40894613012.

It is not an unprimeable number, because it can be changed into a prime (21031649801) 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, 566732 + ... + 602700.

It is an arithmetic number, because the mean of its divisors is an integer number (851301990).

Almost surely, 2^21031649804 is an apocalyptic number.

It is an amenable number.

21031649804 is a deficient number, since it is larger than the sum of its proper divisors (19830845716).

21031649804 is a wasteful number, since it uses less digits than its factorization.

21031649804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36218 (or 36216 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 38.

The spelling of 21031649804 in words is "twenty-one billion, thirty-one million, six hundred forty-nine thousand, eight hundred four".