20647388 has 6 divisors (see below), whose sum is σ = 36132936. Its totient is φ = 10323692.

The previous prime is 20647387. The next prime is 20647409. The reversal of 20647388 is 88374602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20647387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2580920 + ... + 2580927.

It is an arithmetic number, because the mean of its divisors is an integer number (6022156).

Almost surely, 2^20647388 is an apocalyptic number.

It is an amenable number.

20647388 is a deficient number, since it is larger than the sum of its proper divisors (15485548).

20647388 is a wasteful number, since it uses less digits than its factorization.

20647388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5161851 (or 5161849 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 38.

The square root of 20647388 is about 4543.9397003041. The cubic root of 20647388 is about 274.3395190930.

The spelling of 20647388 in words is "twenty million, six hundred forty-seven thousand, three hundred eighty-eight".