13047840 has 288 divisors, whose sum is σ = 52009776. Its totient is φ = 2949120.

The previous prime is 13047829. The next prime is 13047863. The reversal of 13047840 is 4874031.

It can be written as a sum of positive squares in 8 ways, for example, as 1838736 + 11209104 = 1356^2 + 3348^2 .

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×13047840² = 340492257331200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 318220 + ... + 318260.

Almost surely, 2^13047840 is an apocalyptic number.

13047840 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 13047840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26004888).

13047840 is an abundant number, since it is smaller than the sum of its proper divisors (38961936).

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

13047840 is a wasteful number, since it uses less digits than its factorization.

13047840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 13047840 is about 3612.1793975383. The cubic root of 13047840 is about 235.4215460741.

The spelling of 13047840 in words is "thirteen million, forty-seven thousand, eight hundred forty".