21142454 has 8 divisors (see below), whose sum is σ = 32115360. Its totient is φ = 10437336.

The previous prime is 21142447. The next prime is 21142463. The reversal of 21142454 is 45424112.

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

It is a super-2 number, since 2×21142454² = 894006722284232, which contains 22 as substring.

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 3 ways as a sum of consecutive naturals, for example, 66749 + ... + 67064.

It is an arithmetic number, because the mean of its divisors is an integer number (4014420).

Almost surely, 2^21142454 is an apocalyptic number.

21142454 is a deficient number, since it is larger than the sum of its proper divisors (10972906).

21142454 is a wasteful number, since it uses less digits than its factorization.

21142454 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133894.

The product of its digits is 1280, while the sum is 23.

The square root of 21142454 is about 4598.0924305629. The cubic root of 21142454 is about 276.5148532450.

Adding to 21142454 its reverse (45424112), we get a palindrome (66566566).

The spelling of 21142454 in words is "twenty-one million, one hundred forty-two thousand, four hundred fifty-four".