72021543 has 16 divisors (see below), whose sum is σ = 107315712. Its totient is φ = 42584000.

The previous prime is 72021539. The next prime is 72021557. The reversal of 72021543 is 34512027.

It is a cyclic number.

It is not a de Polignac number, because 72021543 - 2² = 72021539 is a prime.

It is a super-2 number, since 2×72021543² = 10374205312201698, which contains 22 as substring.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72021563) 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, 25263 + ... + 27968.

It is an arithmetic number, because the mean of its divisors is an integer number (6707232).

Almost surely, 2^72021543 is an apocalyptic number.

72021543 is a deficient number, since it is larger than the sum of its proper divisors (35294169).

72021543 is a wasteful number, since it uses less digits than its factorization.

72021543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53286.

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 72021543 is about 8486.5507127454. The cubic root of 72021543 is about 416.0582523671.

The spelling of 72021543 in words is "seventy-two million, twenty-one thousand, five hundred forty-three".