21154045 has 8 divisors (see below), whose sum is σ = 27692640. Its totient is φ = 15384720.

The previous prime is 21154039. The next prime is 21154097. The reversal of 21154045 is 54045112.

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

It is not a de Polignac number, because 21154045 - 2⁷ = 21153917 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 192255 + ... + 192364.

It is an arithmetic number, because the mean of its divisors is an integer number (3461580).

Almost surely, 2^21154045 is an apocalyptic number.

It is an amenable number.

21154045 is a deficient number, since it is larger than the sum of its proper divisors (6538595).

21154045 is a wasteful number, since it uses less digits than its factorization.

21154045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384635.

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 21154045 is about 4599.3526718442. The cubic root of 21154045 is about 276.5653755752.

Adding to 21154045 its reverse (54045112), we get a palindrome (75199157).

The spelling of 21154045 in words is "twenty-one million, one hundred fifty-four thousand, forty-five".