1921550436 has 72 divisors (see below), whose sum is σ = 5237791104. Its totient is φ = 590466240.

The previous prime is 1921550369. The next prime is 1921550437. The reversal of 1921550436 is 6340551291.

1921550436 is a `hidden beast` number, since 1 + 9 + 215 + 5 + 0 + 436 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 1921550436.

It is not an unprimeable number, because it can be changed into a prime (1921550437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 424095 + ... + 428601.

Almost surely, 2^1921550436 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1921550436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2618895552).

1921550436 is an abundant number, since it is smaller than the sum of its proper divisors (3316240668).

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

1921550436 is a wasteful number, since it uses less digits than its factorization.

1921550436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5441 (or 5436 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 1921550436 is about 43835.4928796289. The cubic root of 1921550436 is about 1243.2274655038.

The spelling of 1921550436 in words is "one billion, nine hundred twenty-one million, five hundred fifty thousand, four hundred thirty-six".