2457640 has 16 divisors (see below), whose sum is σ = 5529780. Its totient is φ = 983040.

The previous prime is 2457617. The next prime is 2457641. The reversal of 2457640 is 467542.

It can be written as a sum of positive squares in 2 ways, for example, as 2427364 + 30276 = 1558^2 + 174^2 .

It is a junction number, because it is equal to n+sod(n) for n = 2457599 and 2457608.

It is not an unprimeable number, because it can be changed into a prime (2457641) 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, 30681 + ... + 30760.

2^2457640 is an apocalyptic number.

2457640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2457640 is an abundant number, since it is smaller than the sum of its proper divisors (3072140).

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

2457640 is a wasteful number, since it uses less digits than its factorization.

2457640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61452 (or 61448 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 28.

The square root of 2457640 is about 1567.6861930884. The cubic root of 2457640 is about 134.9499585907.

The spelling of 2457640 in words is "two million, four hundred fifty-seven thousand, six hundred forty".