1211038920 has 288 divisors, whose sum is σ = 4931592120. Its totient is φ = 255467520.

The previous prime is 1211038919. The next prime is 1211038957. The reversal of 1211038920 is 298301121.

It can be written as a sum of positive squares in 4 ways, for example, as 508682916 + 702356004 = 22554^2 + 26502^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 226680 + ... + 231960.

Almost surely, 2^1211038920 is an apocalyptic number.

1211038920 is a gapful number since it is divisible by the number (10) 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 1211038920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2465796060).

1211038920 is an abundant number, since it is smaller than the sum of its proper divisors (3720553200).

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

1211038920 is a wasteful number, since it uses less digits than its factorization.

1211038920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5325 (or 5311 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 1211038920 is about 34799.9844827552. The cubic root of 1211038920 is about 1065.9071289918.

The spelling of 1211038920 in words is "one billion, two hundred eleven million, thirty-eight thousand, nine hundred twenty".