20201209984 has 16 divisors (see below), whose sum is σ = 40244598270. Its totient is φ = 10100604928.

The previous prime is 20201209981. The next prime is 20201210033. The reversal of 20201209984 is 48990210202.

It can be written as a sum of positive squares in only one way, i.e., 14321387584 + 5879822400 = 119672^2 + 76680^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a super-2 number, since 2×20201209984² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20201209981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78910849 + ... + 78911104.

Almost surely, 2^20201209984 is an apocalyptic number.

It is an amenable number.

20201209984 is a deficient number, since it is larger than the sum of its proper divisors (20043388286).

20201209984 is an equidigital number, since it uses as much as digits as its factorization.

20201209984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157821967 (or 157821955 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The spelling of 20201209984 in words is "twenty billion, two hundred one million, two hundred nine thousand, nine hundred eighty-four".