21253948 has 12 divisors (see below), whose sum is σ = 37358440. Its totient is φ = 10580112.

The previous prime is 21253943. The next prime is 21253957. The reversal of 21253948 is 84935212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21253943) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10686 + ... + 12517.

Almost surely, 2^21253948 is an apocalyptic number.

It is an amenable number.

21253948 is a deficient number, since it is larger than the sum of its proper divisors (16104492).

21253948 is a wasteful number, since it uses less digits than its factorization.

21253948 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23436 (or 23434 counting only the distinct ones).

The product of its digits is 17280, while the sum is 34.

The square root of 21253948 is about 4610.2004294824. The cubic root of 21253948 is about 277.0000651644. Note that the first 4 decimals are identical.

It can be divided in two parts, 21253 and 948, that added together give a square (22201 = 149²).

The spelling of 21253948 in words is "twenty-one million, two hundred fifty-three thousand, nine hundred forty-eight".