1211013990 has 80 divisors (see below), whose sum is σ = 3295697328. Its totient is φ = 319028544.

The previous prime is 1211013953. The next prime is 1211014043. The reversal of 1211013990 is 993101121.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 58224 + ... + 76236.

Almost surely, 2^1211013990 is an apocalyptic number.

1211013990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211013990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1647848664).

1211013990 is an abundant number, since it is smaller than the sum of its proper divisors (2084683338).

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

1211013990 is a wasteful number, since it uses less digits than its factorization.

1211013990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18115 (or 18106 counting only the distinct ones).

The product of its (nonzero) digits is 486, while the sum is 27.

The square root of 1211013990 is about 34799.6262910969. The cubic root of 1211013990 is about 1065.8998148181.

The spelling of 1211013990 in words is "one billion, two hundred eleven million, thirteen thousand, nine hundred ninety".