20421644255610 has 96 divisors (see below), whose sum is σ = 53310101902848. Its totient is φ = 5004324000000.

The previous prime is 20421644255543. The next prime is 20421644255633. The reversal of 20421644255610 is 1655244612402.

It is a super-2 number, since 2×20421644255610² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 7900641 + ... + 10161860.

It is an arithmetic number, because the mean of its divisors is an integer number (555313561488).

Almost surely, 2^{20421644255610} is an apocalyptic number.

20421644255610 is an abundant number, since it is smaller than the sum of its proper divisors (32888457647238).

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

20421644255610 is a wasteful number, since it uses less digits than its factorization.

20421644255610 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18062760 (or 18062747 counting only the distinct ones).

The product of its (nonzero) digits is 460800, while the sum is 42.

The spelling of 20421644255610 in words is "twenty trillion, four hundred twenty-one billion, six hundred forty-four million, two hundred fifty-five thousand, six hundred ten".