21692320 has 48 divisors (see below), whose sum is σ = 55195560. Its totient is φ = 8008704.

The previous prime is 21692309. The next prime is 21692329. The reversal of 21692320 is 2329612.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 19607184 + 2085136 = 4428^2 + 1444^2 .

It is not an unprimeable number, because it can be changed into a prime (21692329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3135 + ... + 7294.

Almost surely, 2^21692320 is an apocalyptic number.

21692320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21692320 is an abundant number, since it is smaller than the sum of its proper divisors (33503240).

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

21692320 is a wasteful number, since it uses less digits than its factorization.

21692320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10457 (or 10449 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 21692320 is about 4657.5014761136. The cubic root of 21692320 is about 278.8915359705.

It can be divided in two parts, 2169 and 2320, that added together give a square (4489 = 67²).

The spelling of 21692320 in words is "twenty-one million, six hundred ninety-two thousand, three hundred twenty".