20634247 has 16 divisors (see below), whose sum is σ = 22464000. Its totient is φ = 18892224.

The previous prime is 20634241. The next prime is 20634259. The reversal of 20634247 is 74243602.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20634247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20634241) 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, 88443 + ... + 88675.

It is an arithmetic number, because the mean of its divisors is an integer number (1404000).

Almost surely, 2^20634247 is an apocalyptic number.

20634247 is a deficient number, since it is larger than the sum of its proper divisors (1829753).

20634247 is a wasteful number, since it uses less digits than its factorization.

20634247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390.

The product of its (nonzero) digits is 8064, while the sum is 28.

The square root of 20634247 is about 4542.4934782562. The cubic root of 20634247 is about 274.2813057456.

Adding to 20634247 its reverse (74243602), we get a palindrome (94877849).

It can be divided in two parts, 206 and 34247, that added together give a triangular number (34453 = T₂₆₂).

The spelling of 20634247 in words is "twenty million, six hundred thirty-four thousand, two hundred forty-seven".