1565632640 has 128 divisors (see below), whose sum is σ = 4397440320. Its totient is φ = 525496320.

The previous prime is 1565632639. The next prime is 1565632669. The reversal of 1565632640 is 462365651.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (128).

It is a junction number, because it is equal to n+sod(n) for n = 1565632594 and 1565632603.

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, 82967 + ... + 100073.

Almost surely, 2^1565632640 is an apocalyptic number.

1565632640 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 1565632640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2198720160).

1565632640 is an abundant number, since it is smaller than the sum of its proper divisors (2831807680).

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

1565632640 is a wasteful number, since it uses less digits than its factorization.

1565632640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17150 (or 17138 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 38.

The square root of 1565632640 is about 39568.0760209541. The cubic root of 1565632640 is about 1161.1721801544.

The spelling of 1565632640 in words is "one billion, five hundred sixty-five million, six hundred thirty-two thousand, six hundred forty".