1564440020 has 48 divisors (see below), whose sum is σ = 3859688448. Its totient is φ = 525125760.

The previous prime is 1564440019. The next prime is 1564440023. The reversal of 1564440020 is 200444651.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1564440023) 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, 270644 + ... + 276363.

It is an arithmetic number, because the mean of its divisors is an integer number (80410176).

Almost surely, 2^1564440020 is an apocalyptic number.

1564440020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1564440020 is an abundant number, since it is smaller than the sum of its proper divisors (2295248428).

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

1564440020 is a wasteful number, since it uses less digits than its factorization.

1564440020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 547040 (or 547038 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 1564440020 is about 39553.0026673071. The cubic root of 1564440020 is about 1160.8772644524.

Adding to 1564440020 its reverse (200444651), we get a palindrome (1764884671).

The spelling of 1564440020 in words is "one billion, five hundred sixty-four million, four hundred forty thousand, twenty".