1212115900 has 72 divisors (see below), whose sum is σ = 2779197120. Its totient is φ = 458115840.

The previous prime is 1212115873. The next prime is 1212115973. The reversal of 1212115900 is 95112121.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 131854 + ... + 140746.

It is an arithmetic number, because the mean of its divisors is an integer number (38599960).

Almost surely, 2^1212115900 is an apocalyptic number.

1212115900 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 1212115900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1389598560).

1212115900 is an abundant number, since it is smaller than the sum of its proper divisors (1567081220).

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

1212115900 is a wasteful number, since it uses less digits than its factorization.

1212115900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8983 (or 8976 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 22.

The square root of 1212115900 is about 34815.4549015233. The cubic root of 1212115900 is about 1066.2230066828.

The spelling of 1212115900 in words is "one billion, two hundred twelve million, one hundred fifteen thousand, nine hundred".