1211323020 has 48 divisors (see below), whose sum is σ = 3483378528. Its totient is φ = 314288640.

The previous prime is 1211323007. The next prime is 1211323031. The reversal of 1211323020 is 203231121.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 270601 + ... + 275040.

It is an arithmetic number, because the mean of its divisors is an integer number (72570386).

Almost surely, 2^1211323020 is an apocalyptic number.

1211323020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211323020 is an abundant number, since it is smaller than the sum of its proper divisors (2272055508).

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

1211323020 is a wasteful number, since it uses less digits than its factorization.

1211323020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 545690 (or 545688 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 1211323020 is about 34804.0661417599. The cubic root of 1211323020 is about 1065.9904735575.

Adding to 1211323020 its reverse (203231121), we get a palindrome (1414554141).

The spelling of 1211323020 in words is "one billion, two hundred eleven million, three hundred twenty-three thousand, twenty".