21304661020 has 24 divisors (see below), whose sum is σ = 45691700544. Its totient is φ = 8340547776.

The previous prime is 21304661017. The next prime is 21304661023. The reversal of 21304661020 is 2016640312.

It is an interprime number because it is at equal distance from previous prime (21304661017) and next prime (21304661023).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21304661023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11331327 + ... + 11333206.

It is an arithmetic number, because the mean of its divisors is an integer number (1903820856).

Almost surely, 2^21304661020 is an apocalyptic number.

21304661020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21304661020 is an abundant number, since it is smaller than the sum of its proper divisors (24387039524).

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

21304661020 is a wasteful number, since it uses less digits than its factorization.

21304661020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22664589 (or 22664587 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 25.

The spelling of 21304661020 in words is "twenty-one billion, three hundred four million, six hundred sixty-one thousand, twenty".