1543640016021 has 16 divisors (see below), whose sum is σ = 2115023588544. Its totient is φ = 1000706742144.

The previous prime is 1543640016019. The next prime is 1543640016031. The reversal of 1543640016021 is 1206100463451.

It is not a de Polignac number, because 1543640016021 - 2¹ = 1543640016019 is a prime.

It is a super-2 number, since 2×1543640016021² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1543640016031) 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, 3786240 + ... + 4174073.

It is an arithmetic number, because the mean of its divisors is an integer number (132188974284).

Almost surely, 2^{1543640016021} is an apocalyptic number.

It is an amenable number.

1543640016021 is a deficient number, since it is larger than the sum of its proper divisors (571383572523).

1543640016021 is a wasteful number, since it uses less digits than its factorization.

1543640016021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7962100.

The product of its (nonzero) digits is 17280, while the sum is 33.

Adding to 1543640016021 its reverse (1206100463451), we get a palindrome (2749740479472).

The spelling of 1543640016021 in words is "one trillion, five hundred forty-three billion, six hundred forty million, sixteen thousand, twenty-one".