1565457920 has 160 divisors (see below), whose sum is σ = 4281475968. Its totient is φ = 543817728.

The previous prime is 1565457911. The next prime is 1565457923. The reversal of 1565457920 is 297545651.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (160).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1565457923) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 564377 + ... + 567143.

Almost surely, 2^1565457920 is an apocalyptic number.

1565457920 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 1565457920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2140737984).

1565457920 is an abundant number, since it is smaller than the sum of its proper divisors (2716018048).

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

1565457920 is a wasteful number, since it uses less digits than its factorization.

1565457920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2820 (or 2804 counting only the distinct ones).

The product of its (nonzero) digits is 378000, while the sum is 44.

The square root of 1565457920 is about 39565.8681188724. The cubic root of 1565457920 is about 1161.1289840803.

The spelling of 1565457920 in words is "one billion, five hundred sixty-five million, four hundred fifty-seven thousand, nine hundred twenty".