21401274 has 32 divisors (see below), whose sum is σ = 43868160. Its totient is φ = 6958512.

The previous prime is 21401269. The next prime is 21401287. The reversal of 21401274 is 47210412.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21401274.

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 15 ways as a sum of consecutive naturals, for example, 55687 + ... + 56069.

It is an arithmetic number, because the mean of its divisors is an integer number (1370880).

Almost surely, 2^21401274 is an apocalyptic number.

21401274 is an abundant number, since it is smaller than the sum of its proper divisors (22466886).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21401274 is a wasteful number, since it uses less digits than its factorization.

21401274 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 594.

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 21401274 is about 4626.1510999966. The cubic root of 21401274 is about 277.6386191624.

Adding to 21401274 its reverse (47210412), we get a palindrome (68611686).

The spelling of 21401274 in words is "twenty-one million, four hundred one thousand, two hundred seventy-four".