21627154 has 4 divisors (see below), whose sum is σ = 32440734. Its totient is φ = 10813576.

The previous prime is 21627139. The next prime is 21627157. The reversal of 21627154 is 45172612.

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

It can be written as a sum of positive squares in only one way, i.e., 21372129 + 255025 = 4623^2 + 505^2 .

It is not an unprimeable number, because it can be changed into a prime (21627157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5406787 + ... + 5406790.

Almost surely, 2^21627154 is an apocalyptic number.

21627154 is a deficient number, since it is larger than the sum of its proper divisors (10813580).

21627154 is a wasteful number, since it uses less digits than its factorization.

21627154 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10813579.

The product of its digits is 3360, while the sum is 28.

The square root of 21627154 is about 4650.5004031824. The cubic root of 21627154 is about 278.6119827249.

Adding to 21627154 its reverse (45172612), we get a palindrome (66799766).

It can be divided in two parts, 2162 and 7154, that added together give a triangular number (9316 = T₁₃₆).

The spelling of 21627154 in words is "twenty-one million, six hundred twenty-seven thousand, one hundred fifty-four".