21011738 has 16 divisors (see below), whose sum is σ = 35493120. Its totient is φ = 9242400.

The previous prime is 21011713. The next prime is 21011741. The reversal of 21011738 is 83711012.

It is a happy number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14723 + ... + 16086.

It is an arithmetic number, because the mean of its divisors is an integer number (2218320).

Almost surely, 2^21011738 is an apocalyptic number.

21011738 is a deficient number, since it is larger than the sum of its proper divisors (14481382).

21011738 is a wasteful number, since it uses less digits than its factorization.

21011738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30853.

The product of its (nonzero) digits is 336, while the sum is 23.

The square root of 21011738 is about 4583.8562368381. The cubic root of 21011738 is about 275.9438116383.

The spelling of 21011738 in words is "twenty-one million, eleven thousand, seven hundred thirty-eight".