21729962 has 8 divisors (see below), whose sum is σ = 32624100. Its totient is φ = 10855264.

The previous prime is 21729941. The next prime is 21729971. The reversal of 21729962 is 26992712.

It can be written as a sum of positive squares in 2 ways, for example, as 21724921 + 5041 = 4661^2 + 71^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1637 + ... + 6792.

Almost surely, 2^21729962 is an apocalyptic number.

21729962 is a deficient number, since it is larger than the sum of its proper divisors (10894138).

21729962 is a wasteful number, since it uses less digits than its factorization.

21729962 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9720.

The product of its digits is 27216, while the sum is 38.

The square root of 21729962 is about 4661.5407324188. The cubic root of 21729962 is about 279.0527599850.

The spelling of 21729962 in words is "twenty-one million, seven hundred twenty-nine thousand, nine hundred sixty-two".