1921989237 has 8 divisors (see below), whose sum is σ = 2928745536. Its totient is φ = 1098279552.

The previous prime is 1921989221. The next prime is 1921989259. The reversal of 1921989237 is 7329891291.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1921989237 - 2⁴ = 1921989221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1921989237.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1921989217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45761628 + ... + 45761669.

It is an arithmetic number, because the mean of its divisors is an integer number (366093192).

Almost surely, 2^1921989237 is an apocalyptic number.

It is an amenable number.

1921989237 is a deficient number, since it is larger than the sum of its proper divisors (1006756299).

1921989237 is an equidigital number, since it uses as much as digits as its factorization.

1921989237 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91523307.

The product of its digits is 489888, while the sum is 51.

The square root of 1921989237 is about 43840.4976819379. The cubic root of 1921989237 is about 1243.3220918578.

The spelling of 1921989237 in words is "one billion, nine hundred twenty-one million, nine hundred eighty-nine thousand, two hundred thirty-seven".