21353510500 has 96 divisors (see below), whose sum is σ = 55615891968. Its totient is φ = 7002864000.

The previous prime is 21353510471. The next prime is 21353510509. The reversal of 21353510500 is 501535312.

It is a super-2 number, since 2×21353510500² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (21353510509) 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 31 ways as a sum of consecutive naturals, for example, 52131 + ... + 213130.

It is an arithmetic number, because the mean of its divisors is an integer number (579332208).

Almost surely, 2^21353510500 is an apocalyptic number.

21353510500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21353510500 is an abundant number, since it is smaller than the sum of its proper divisors (34262381468).

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

21353510500 is a wasteful number, since it uses less digits than its factorization.

21353510500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265310 (or 265298 counting only the distinct ones).

The product of its (nonzero) digits is 2250, while the sum is 25.

The spelling of 21353510500 in words is "twenty-one billion, three hundred fifty-three million, five hundred ten thousand, five hundred".