1625554440 has 256 divisors, whose sum is σ = 5839257600. Its totient is φ = 401068800.

The previous prime is 1625554391. The next prime is 1625554451. The reversal of 1625554440 is 444555261.

1625554440 is a `hidden beast` number, since 1 + 62 + 5 + 554 + 4 + 40 = 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 = 1625554395 and 1625554404.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 768985 + ... + 771095.

It is an arithmetic number, because the mean of its divisors is an integer number (22809600).

Almost surely, 2^1625554440 is an apocalyptic number.

1625554440 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 1625554440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2919628800).

1625554440 is an abundant number, since it is smaller than the sum of its proper divisors (4213703160).

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

1625554440 is a wasteful number, since it uses less digits than its factorization.

1625554440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2185 (or 2175 counting only the distinct ones).

The product of its (nonzero) digits is 96000, while the sum is 36.

The square root of 1625554440 is about 40318.1651368214. The cubic root of 1625554440 is about 1175.8010388105.

The spelling of 1625554440 in words is "one billion, six hundred twenty-five million, five hundred fifty-four thousand, four hundred forty".