1644102155423 has 16 divisors (see below), whose sum is σ = 2038957003776. Its totient is φ = 1290898084320.

The previous prime is 1644102155383. The next prime is 1644102155473. The reversal of 1644102155423 is 3245512014461.

It is not a de Polignac number, because 1644102155423 - 2¹⁰ = 1644102154399 is a prime.

It is a super-3 number, since 3×1644102155423³ (a number of 38 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1644102155473) 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, 68946311 + ... + 68970152.

It is an arithmetic number, because the mean of its divisors is an integer number (127434812736).

Almost surely, 2^{1644102155423} is an apocalyptic number.

1644102155423 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

1644102155423 is a deficient number, since it is larger than the sum of its proper divisors (394854848353).

1644102155423 is a wasteful number, since it uses less digits than its factorization.

1644102155423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137916614.

The product of its (nonzero) digits is 115200, while the sum is 38.

Adding to 1644102155423 its reverse (3245512014461), we get a palindrome (4889614169884).

The spelling of 1644102155423 in words is "one trillion, six hundred forty-four billion, one hundred two million, one hundred fifty-five thousand, four hundred twenty-three".