21554043 has 8 divisors (see below), whose sum is σ = 32844288. Its totient is φ = 12316584.

The previous prime is 21554041. The next prime is 21554063. The reversal of 21554043 is 34045512.

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

It is not a de Polignac number, because 21554043 - 2¹ = 21554041 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21554041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 513171 + ... + 513212.

It is an arithmetic number, because the mean of its divisors is an integer number (4105536).

Almost surely, 2^21554043 is an apocalyptic number.

21554043 is a deficient number, since it is larger than the sum of its proper divisors (11290245).

21554043 is a wasteful number, since it uses less digits than its factorization.

21554043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1026393.

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 21554043 is about 4642.6331967968. The cubic root of 21554043 is about 278.2976772744.

Adding to 21554043 its reverse (34045512), we get a palindrome (55599555).

The spelling of 21554043 in words is "twenty-one million, five hundred fifty-four thousand, forty-three".