1625388880 has 20 divisors (see below), whose sum is σ = 3779029332. Its totient is φ = 650155520.

The previous prime is 1625388847. The next prime is 1625388883. The reversal of 1625388880 is 888835261.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 690007824 + 935381056 = 26268^2 + 30584^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×1625388880² = 5283778022455308800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1625388883) 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, 10158601 + ... + 10158760.

Almost surely, 2^1625388880 is an apocalyptic number.

1625388880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1625388880 is an abundant number, since it is smaller than the sum of its proper divisors (2153640452).

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

1625388880 is a wasteful number, since it uses less digits than its factorization.

1625388880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20317374 (or 20317368 counting only the distinct ones).

The product of its (nonzero) digits is 737280, while the sum is 49.

The square root of 1625388880 is about 40316.1119157093. Note that the first 3 decimals coincide. The cubic root of 1625388880 is about 1175.7611196657.

The spelling of 1625388880 in words is "one billion, six hundred twenty-five million, three hundred eighty-eight thousand, eight hundred eighty".