1625257440 has 192 divisors, whose sum is σ = 5885006400. Its totient is φ = 418424832.

The previous prime is 1625257393. The next prime is 1625257451. The reversal of 1625257440 is 447525261.

It is a happy number.

1625257440 is a `hidden beast` number, since 1 + 62 + 525 + 74 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1625257395 and 1625257404.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 118794 + ... + 131766.

It is an arithmetic number, because the mean of its divisors is an integer number (30651075).

Almost surely, 2^1625257440 is an apocalyptic number.

1625257440 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 1625257440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2942503200).

1625257440 is an abundant number, since it is smaller than the sum of its proper divisors (4259748960).

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

1625257440 is a wasteful number, since it uses less digits than its factorization.

1625257440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13026 (or 13012 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 36.

The square root of 1625257440 is about 40314.4817652416. The cubic root of 1625257440 is about 1175.7294254643.

The spelling of 1625257440 in words is "one billion, six hundred twenty-five million, two hundred fifty-seven thousand, four hundred forty".