201211920 has 480 divisors, whose sum is σ = 864444672. Its totient is φ = 40808448.

The previous prime is 201211909. The next prime is 201211943. The reversal of 201211920 is 29112102.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 201211893 and 201211902.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2424199 + ... + 2424281.

Almost surely, 2^201211920 is an apocalyptic number.

201211920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

201211920 is the 8190-th octagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 201211920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (432222336).

201211920 is an abundant number, since it is smaller than the sum of its proper divisors (663232752).

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

201211920 is a wasteful number, since it uses less digits than its factorization.

201211920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159 (or 150 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 201211920 is about 14184.9187519703. The cubic root of 201211920 is about 585.9823949174.

The spelling of 201211920 in words is "two hundred one million, two hundred eleven thousand, nine hundred twenty".