19913505 has 16 divisors (see below), whose sum is σ = 32173440. Its totient is φ = 10516608.

The previous prime is 19913497. The next prime is 19913507. The reversal of 19913505 is 50531991.

It is not a de Polignac number, because 19913505 - 2³ = 19913497 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19913507) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4900 + ... + 7989.

It is an arithmetic number, because the mean of its divisors is an integer number (2010840).

Almost surely, 2^19913505 is an apocalyptic number.

19913505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19913505 is a deficient number, since it is larger than the sum of its proper divisors (12259935).

19913505 is a wasteful number, since it uses less digits than its factorization.

19913505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13000.

The product of its (nonzero) digits is 6075, while the sum is 33.

The square root of 19913505 is about 4462.4550417903. The cubic root of 19913505 is about 271.0498902806.

The spelling of 19913505 in words is "nineteen million, nine hundred thirteen thousand, five hundred five".