3129840 has 240 divisors, whose sum is σ = 12999168. Its totient is φ = 684288.

The previous prime is 3129839. The next prime is 3129859. The reversal of 3129840 is 489213.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

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, 136069 + ... + 136091.

Almost surely, 2^3129840 is an apocalyptic number.

3129840 is a gapful number since it is divisible by the number (30) 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 3129840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6499584).

3129840 is an abundant number, since it is smaller than the sum of its proper divisors (9869328).

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

3129840 is a wasteful number, since it uses less digits than its factorization.

3129840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58 (or 40 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 3129840 is about 1769.1353820440. The cubic root of 3129840 is about 146.2763266216.

It can be divided in two parts, 3129 and 840, that added together give a square (3969 = 63²).

The spelling of 3129840 in words is "three million, one hundred twenty-nine thousand, eight hundred forty".