21316149 has 16 divisors (see below), whose sum is σ = 31873600. Its totient is φ = 14078448.

The previous prime is 21316133. The next prime is 21316153. The reversal of 21316149 is 94161312.

It is not a de Polignac number, because 21316149 - 2⁴ = 21316133 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21316109) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 679 + ... + 6564.

It is an arithmetic number, because the mean of its divisors is an integer number (1992100).

Almost surely, 2^21316149 is an apocalyptic number.

It is an amenable number.

21316149 is a deficient number, since it is larger than the sum of its proper divisors (10557451).

21316149 is a wasteful number, since it uses less digits than its factorization.

21316149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7361 (or 7355 counting only the distinct ones).

The product of its digits is 1296, while the sum is 27.

The square root of 21316149 is about 4616.9415200975. The cubic root of 21316149 is about 277.2700212908.

The spelling of 21316149 in words is "twenty-one million, three hundred sixteen thousand, one hundred forty-nine".