20999748 has 48 divisors (see below), whose sum is σ = 61092864. Its totient is φ = 5454240.

The previous prime is 20999729. The next prime is 20999767. The reversal of 20999748 is 84799902.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20999729) and next prime (20999767).

It is a junction number, because it is equal to n+sod(n) for n = 20999697 and 20999706.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10440 + ... + 12287.

It is an arithmetic number, because the mean of its divisors is an integer number (1272768).

Almost surely, 2^20999748 is an apocalyptic number.

20999748 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

20999748 is an abundant number, since it is smaller than the sum of its proper divisors (40093116).

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

20999748 is a wasteful number, since it uses less digits than its factorization.

20999748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22752 (or 22750 counting only the distinct ones).

The product of its (nonzero) digits is 326592, while the sum is 48.

The square root of 20999748 is about 4582.5481994192. The cubic root of 20999748 is about 275.8913140640.

The spelling of 20999748 in words is "twenty million, nine hundred ninety-nine thousand, seven hundred forty-eight".