13921540 has 12 divisors (see below), whose sum is σ = 29235276. Its totient is φ = 5568608.

The previous prime is 13921519. The next prime is 13921549. The reversal of 13921540 is 4512931.

It can be written as a sum of positive squares in 2 ways, for example, as 9784384 + 4137156 = 3128^2 + 2034^2 .

It is not an unprimeable number, because it can be changed into a prime (13921549) 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, 348019 + ... + 348058.

It is an arithmetic number, because the mean of its divisors is an integer number (2436273).

Almost surely, 2^13921540 is an apocalyptic number.

13921540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13921540 is an abundant number, since it is smaller than the sum of its proper divisors (15313736).

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

13921540 is a wasteful number, since it uses less digits than its factorization.

13921540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696086 (or 696084 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 13921540 is about 3731.1579971907. The cubic root of 13921540 is about 240.5631451737.

The spelling of 13921540 in words is "thirteen million, nine hundred twenty-one thousand, five hundred forty".