20421564646000 has 160 divisors (see below), whose sum is σ = 56461103008128. Its totient is φ = 6998258995200.

The previous prime is 20421564645973. The next prime is 20421564646027. The reversal of 20421564646000 is 64646512402.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20421564645973) and next prime (20421564646027).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is an unprimeable number.

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, 28386744 + ... + 29097256.

Almost surely, 2^{20421564646000} is an apocalyptic number.

20421564646000 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 20421564646000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28230551504064).

20421564646000 is an abundant number, since it is smaller than the sum of its proper divisors (36039538362128).

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

20421564646000 is a wasteful number, since it uses less digits than its factorization.

20421564646000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 712596 (or 712580 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 40.

The spelling of 20421564646000 in words is "twenty trillion, four hundred twenty-one billion, five hundred sixty-four million, six hundred forty-six thousand".