21154006 has 4 divisors (see below), whose sum is σ = 31731012. Its totient is φ = 10577002.

The previous prime is 21153971. The next prime is 21154019. The reversal of 21154006 is 60045112.

21154006 is nontrivially palindromic in base 15.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5288500 + ... + 5288503.

It is an arithmetic number, because the mean of its divisors is an integer number (7932753).

Almost surely, 2^21154006 is an apocalyptic number.

21154006 is a deficient number, since it is larger than the sum of its proper divisors (10577006).

21154006 is a wasteful number, since it uses less digits than its factorization.

21154006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10577005.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 21154006 is about 4599.3484321151. The cubic root of 21154006 is about 276.5652056147.

Adding to 21154006 its reverse (60045112), we get a palindrome (81199118).

The spelling of 21154006 in words is "twenty-one million, one hundred fifty-four thousand, six".