21299948 has 6 divisors (see below), whose sum is σ = 37274916. Its totient is φ = 10649972.

The previous prime is 21299947. The next prime is 21299953. The reversal of 21299948 is 84999212.

It is a junction number, because it is equal to n+sod(n) for n = 21299899 and 21299908.

It is not an unprimeable number, because it can be changed into a prime (21299947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2662490 + ... + 2662497.

It is an arithmetic number, because the mean of its divisors is an integer number (6212486).

Almost surely, 2^21299948 is an apocalyptic number.

It is an amenable number.

21299948 is a deficient number, since it is larger than the sum of its proper divisors (15974968).

21299948 is a wasteful number, since it uses less digits than its factorization.

21299948 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5324991 (or 5324989 counting only the distinct ones).

The product of its digits is 93312, while the sum is 44.

The square root of 21299948 is about 4615.1866701142. The cubic root of 21299948 is about 277.1997585972.

The spelling of 21299948 in words is "twenty-one million, two hundred ninety-nine thousand, nine hundred forty-eight".