1644156530421 has 8 divisors (see below), whose sum is σ = 2196785345280. Its totient is φ = 1093816034592.

The previous prime is 1644156530413. The next prime is 1644156530477. The reversal of 1644156530421 is 1240356514461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1644156530421 - 2³ = 1644156530413 is a prime.

It is a super-3 number, since 3×1644156530421³ (a number of 38 digits) contains 333 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1644156530321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 572078080 + ... + 572080953.

It is an arithmetic number, because the mean of its divisors is an integer number (274598168160).

Almost surely, 2^{1644156530421} is an apocalyptic number.

It is an amenable number.

1644156530421 is a deficient number, since it is larger than the sum of its proper divisors (552628814859).

1644156530421 is a wasteful number, since it uses less digits than its factorization.

1644156530421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1144159515.

The product of its (nonzero) digits is 345600, while the sum is 42.

The spelling of 1644156530421 in words is "one trillion, six hundred forty-four billion, one hundred fifty-six million, five hundred thirty thousand, four hundred twenty-one".