7397840 has 80 divisors (see below), whose sum is σ = 18808320. Its totient is φ = 2695680.

The previous prime is 7397801. The next prime is 7397851. The reversal of 7397840 is 487937.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a junction number, because it is equal to n+sod(n) for n = 7397794 and 7397803.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47042 + ... + 47198.

It is an arithmetic number, because the mean of its divisors is an integer number (235104).

Almost surely, 2^7397840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7397840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9404160).

7397840 is an abundant number, since it is smaller than the sum of its proper divisors (11410480).

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

7397840 is a wasteful number, since it uses less digits than its factorization.

7397840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220 (or 214 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 38.

The square root of 7397840 is about 2719.8970568755. The cubic root of 7397840 is about 194.8505539151.

Subtracting from 7397840 its reverse (487937), we obtain a triangular number (6909903 = T₃₇₁₇).

The spelling of 7397840 in words is "seven million, three hundred ninety-seven thousand, eight hundred forty".