1211672220 has 288 divisors, whose sum is σ = 3938264064. Its totient is φ = 277854720.

The previous prime is 1211672213. The next prime is 1211672233. The reversal of 1211672220 is 222761121.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 18084627 + ... + 18084693.

It is an arithmetic number, because the mean of its divisors is an integer number (13674528).

Almost surely, 2^1211672220 is an apocalyptic number.

1211672220 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 1211672220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1969132032).

1211672220 is an abundant number, since it is smaller than the sum of its proper divisors (2726591844).

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

1211672220 is a wasteful number, since it uses less digits than its factorization.

1211672220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201 (or 188 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 1211672220 is about 34809.0824354794. The cubic root of 1211672220 is about 1066.0928982350.

The spelling of 1211672220 in words is "one billion, two hundred eleven million, six hundred seventy-two thousand, two hundred twenty".