19115920 has 20 divisors (see below), whose sum is σ = 44444700. Its totient is φ = 7646336.

The previous prime is 19115891. The next prime is 19115923. The reversal of 19115920 is 2951191.

It can be written as a sum of positive squares in 2 ways, for example, as 3370896 + 15745024 = 1836^2 + 3968^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19115923) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 119395 + ... + 119554.

It is an arithmetic number, because the mean of its divisors is an integer number (2222235).

Almost surely, 2^19115920 is an apocalyptic number.

19115920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19115920 is an abundant number, since it is smaller than the sum of its proper divisors (25328780).

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

19115920 is a wasteful number, since it uses less digits than its factorization.

19115920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238962 (or 238956 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 28.

The square root of 19115920 is about 4372.1756597831. The cubic root of 19115920 is about 267.3817336111.

The spelling of 19115920 in words is "nineteen million, one hundred fifteen thousand, nine hundred twenty".