21405148 has 6 divisors (see below), whose sum is σ = 37459016. Its totient is φ = 10702572.

The previous prime is 21405127. The next prime is 21405149. The reversal of 21405148 is 84150412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21405149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2675640 + ... + 2675647.

Almost surely, 2^21405148 is an apocalyptic number.

It is an amenable number.

21405148 is a deficient number, since it is larger than the sum of its proper divisors (16053868).

21405148 is a wasteful number, since it uses less digits than its factorization.

21405148 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5351291 (or 5351289 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 25.

The square root of 21405148 is about 4626.5697876505. The cubic root of 21405148 is about 277.6553706125.

The spelling of 21405148 in words is "twenty-one million, four hundred five thousand, one hundred forty-eight".