21494777 has 8 divisors (see below), whose sum is σ = 21869664. Its totient is φ = 21122208.

The previous prime is 21494729. The next prime is 21494779. The reversal of 21494777 is 77749412.

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

It is a cyclic number.

It is not a de Polignac number, because 21494777 - 2¹⁴ = 21478393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21494779) 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, 37898 + ... + 38460.

It is an arithmetic number, because the mean of its divisors is an integer number (2733708).

Almost surely, 2^21494777 is an apocalyptic number.

It is an amenable number.

21494777 is a deficient number, since it is larger than the sum of its proper divisors (374887).

21494777 is an equidigital number, since it uses as much as digits as its factorization.

21494777 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1159.

The product of its digits is 98784, while the sum is 41.

The square root of 21494777 is about 4636.2460029640. The cubic root of 21494777 is about 278.0423697132.

The spelling of 21494777 in words is "twenty-one million, four hundred ninety-four thousand, seven hundred seventy-seven".