1919191920 has 80 divisors (see below), whose sum is σ = 5995009152. Its totient is φ = 507869440.

The previous prime is 1919191913. The next prime is 1919191969. The reversal of 1919191920 is 291919191.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

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, 919 + ... + 61961.

Almost surely, 2^1919191920 is an apocalyptic number.

1919191920 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 1919191920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2997504576).

1919191920 is an abundant number, since it is smaller than the sum of its proper divisors (4075817232).

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

1919191920 is a wasteful number, since it uses less digits than its factorization.

1919191920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61190 (or 61184 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 42.

The square root of 1919191920 is about 43808.5827207409. The cubic root of 1919191920 is about 1242.7186103827.

It can be divided in two parts, 19191 and 91920, that added together give a palindrome (111111).

The spelling of 1919191920 in words is "one billion, nine hundred nineteen million, one hundred ninety-one thousand, nine hundred twenty".