20621542500 has 180 divisors, whose sum is σ = 70149066988. Its totient is φ = 5076000000.

The previous prime is 20621542499. The next prime is 20621542507. The reversal of 20621542500 is 524512602.

20621542500 is a `hidden beast` number, since 2 + 0 + 6 + 2 + 154 + 2 + 500 = 666.

It can be written as a sum of positive squares in 10 ways, for example, as 17245467684 + 3376074816 = 131322^2 + 58104^2 .

It is a tau number, because it is divible by the number of its divisors (180).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (20621542507) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 257250 + ... + 327750.

Almost surely, 2^20621542500 is an apocalyptic number.

20621542500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20621542500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35074533494).

20621542500 is an abundant number, since it is smaller than the sum of its proper divisors (49527524488).

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

20621542500 is a wasteful number, since it uses less digits than its factorization.

20621542500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70544 (or 70524 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The spelling of 20621542500 in words is "twenty billion, six hundred twenty-one million, five hundred forty-two thousand, five hundred".