65821972020 has 192 divisors, whose sum is σ = 217723355136. Its totient is φ = 14539714560.

The previous prime is 65821971973. The next prime is 65821972037. The reversal of 65821972020 is 2027912856.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

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 63 ways as a sum of consecutive naturals, for example, 10764484 + ... + 10770596.

It is an arithmetic number, because the mean of its divisors is an integer number (1133975808).

Almost surely, 2^65821972020 is an apocalyptic number.

65821972020 is a gapful number since it is divisible by the number (60) 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 65821972020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108861677568).

65821972020 is an abundant number, since it is smaller than the sum of its proper divisors (151901383116).

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

65821972020 is a wasteful number, since it uses less digits than its factorization.

65821972020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6990 (or 6988 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 42.

The spelling of 65821972020 in words is "sixty-five billion, eight hundred twenty-one million, nine hundred seventy-two thousand, twenty".