43158021 has 16 divisors (see below), whose sum is σ = 59345664. Its totient is φ = 27877824.

The previous prime is 43157981. The next prime is 43158023. The reversal of 43158021 is 12085134.

It is not a de Polignac number, because 43158021 - 2¹⁸ = 42895877 is a prime.

It is a super-2 number, since 2×43158021² = 3725229553272882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 43157982 and 43158000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43158023) 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, 31860 + ... + 33186.

It is an arithmetic number, because the mean of its divisors is an integer number (3709104).

Almost surely, 2^43158021 is an apocalyptic number.

It is an amenable number.

43158021 is a deficient number, since it is larger than the sum of its proper divisors (16187643).

43158021 is a wasteful number, since it uses less digits than its factorization.

43158021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1660.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 43158021 is about 6569.4764631590. The cubic root of 43158021 is about 350.7684368064.

The spelling of 43158021 in words is "forty-three million, one hundred fifty-eight thousand, twenty-one".