1001211988 has 48 divisors (see below), whose sum is σ = 2095236864. Its totient is φ = 409305600.

The previous prime is 1001211961. The next prime is 1001211989. The reversal of 1001211988 is 8891121001.

1001211988 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001211989) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 256306 + ... + 260182.

It is an arithmetic number, because the mean of its divisors is an integer number (43650768).

Almost surely, 2^1001211988 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1001211988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1047618432).

1001211988 is an abundant number, since it is smaller than the sum of its proper divisors (1094024876).

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

1001211988 is a wasteful number, since it uses less digits than its factorization.

1001211988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4312 (or 4310 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 31.

The square root of 1001211988 is about 31641.9340116877. The cubic root of 1001211988 is about 1000.4038328970.

Adding to 1001211988 its reverse (8891121001), we get a palindrome (9892332989).

The spelling of 1001211988 in words is "one billion, one million, two hundred eleven thousand, nine hundred eighty-eight".