21501441020550 has 48 divisors (see below), whose sum is σ = 53922715042320. Its totient is φ = 5669293808640.

The previous prime is 21501441020537. The next prime is 21501441020551. The reversal of 21501441020550 is 5502014410512.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21501441020551) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 805284067 + ... + 805310766.

It is an arithmetic number, because the mean of its divisors is an integer number (1123389896715).

Almost surely, 2^{21501441020550} is an apocalyptic number.

21501441020550 is an abundant number, since it is smaller than the sum of its proper divisors (32421274021770).

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

21501441020550 is a wasteful number, since it uses less digits than its factorization.

21501441020550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1610594937 (or 1610594932 counting only the distinct ones).

The product of its (nonzero) digits is 8000, while the sum is 30.

The spelling of 21501441020550 in words is "twenty-one trillion, five hundred one billion, four hundred forty-one million, twenty thousand, five hundred fifty".