1020191920 has 80 divisors (see below), whose sum is σ = 2592476928. Its totient is φ = 370277120.

The previous prime is 1020191903. The next prime is 1020192059. The reversal of 1020191920 is 291910201.

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

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, 779907 + ... + 781213.

Almost surely, 2^1020191920 is an apocalyptic number.

1020191920 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 1020191920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1296238464).

1020191920 is an abundant number, since it is smaller than the sum of its proper divisors (1572285008).

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

1020191920 is a wasteful number, since it uses less digits than its factorization.

1020191920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2218 (or 2212 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 25.

The square root of 1020191920 is about 31940.4433281694. The cubic root of 1020191920 is about 1006.6858399245.

The spelling of 1020191920 in words is "one billion, twenty million, one hundred ninety-one thousand, nine hundred twenty".