20401010820 has 144 divisors (see below), whose sum is σ = 66917829888. Its totient is φ = 5011276800.

The previous prime is 20401010801. The next prime is 20401010821. The reversal of 20401010820 is 2801010402.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20401010793 and 20401010802.

It is not an unprimeable number, because it can be changed into a prime (20401010821) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 72895 + ... + 214745.

It is an arithmetic number, because the mean of its divisors is an integer number (464707152).

Almost surely, 2^20401010820 is an apocalyptic number.

20401010820 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 20401010820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33458914944).

20401010820 is an abundant number, since it is smaller than the sum of its proper divisors (46516819068).

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

20401010820 is a wasteful number, since it uses less digits than its factorization.

20401010820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141930 (or 141925 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The spelling of 20401010820 in words is "twenty billion, four hundred one million, ten thousand, eight hundred twenty".