21361708 has 6 divisors (see below), whose sum is σ = 37382996. Its totient is φ = 10680852.

The previous prime is 21361619. The next prime is 21361709. The reversal of 21361708 is 80716312.

It is not an unprimeable number, because it can be changed into a prime (21361709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2670210 + ... + 2670217.

Almost surely, 2^21361708 is an apocalyptic number.

It is an amenable number.

21361708 is a deficient number, since it is larger than the sum of its proper divisors (16021288).

21361708 is a wasteful number, since it uses less digits than its factorization.

21361708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5340431 (or 5340429 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 21361708 is about 4621.8727805945. The cubic root of 21361708 is about 277.4674171089.

It can be divided in two parts, 2136 and 1708, that added together give a square (3844 = 62²).

The spelling of 21361708 in words is "twenty-one million, three hundred sixty-one thousand, seven hundred eight".