1564421851944 has 224 divisors, whose sum is σ = 5095061296320. Its totient is φ = 440853850368.

The previous prime is 1564421851943. The next prime is 1564421851963. The reversal of 1564421851944 is 4491581244651.

It is a happy number.

1564421851944 is a `hidden beast` number, since 1 + 5 + 6 + 442 + 1 + 8 + 5 + 194 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (1564421851943) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 2717679 + ... + 3242625.

Almost surely, 2^{1564421851944} is an apocalyptic number.

1564421851944 is a gapful number since it is divisible by the number (14) 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 1564421851944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2547530648160).

1564421851944 is an abundant number, since it is smaller than the sum of its proper divisors (3530639444376).

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

1564421851944 is an equidigital number, since it uses as much as digits as its factorization.

1564421851944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525051 (or 525032 counting only the distinct ones).

The product of its digits is 5529600, while the sum is 54.

The spelling of 1564421851944 in words is "one trillion, five hundred sixty-four billion, four hundred twenty-one million, eight hundred fifty-one thousand, nine hundred forty-four".