13921440 has 192 divisors, whose sum is σ = 49787136. Its totient is φ = 3244032.

The previous prime is 13921429. The next prime is 13921451. The reversal of 13921440 is 4412931.

It is an interprime number because it is at equal distance from previous prime (13921429) and next prime (13921451).

It is a super-3 number, since 3×13921440³ (a number of 22 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 13921440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 143472 + ... + 143568.

It is an arithmetic number, because the mean of its divisors is an integer number (259308).

Almost surely, 2^13921440 is an apocalyptic number.

13921440 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 13921440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24893568).

13921440 is an abundant number, since it is smaller than the sum of its proper divisors (35865696).

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

13921440 is a wasteful number, since it uses less digits than its factorization.

13921440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151 (or 143 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 13921440 is about 3731.1445965012. The cubic root of 13921440 is about 240.5625691749.

The spelling of 13921440 in words is "thirteen million, nine hundred twenty-one thousand, four hundred forty".