20121236 has 6 divisors (see below), whose sum is σ = 35212170. Its totient is φ = 10060616.

The previous prime is 20121193. The next prime is 20121271. The reversal of 20121236 is 63212102.

It can be written as a sum of positive squares in only one way, i.e., 19749136 + 372100 = 4444^2 + 610^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2515151 + ... + 2515158.

It is an arithmetic number, because the mean of its divisors is an integer number (5868695).

Almost surely, 2^20121236 is an apocalyptic number.

It is an amenable number.

20121236 is a deficient number, since it is larger than the sum of its proper divisors (15090934).

20121236 is a wasteful number, since it uses less digits than its factorization.

20121236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5030313 (or 5030311 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 20121236 is about 4485.6700725756. The cubic root of 20121236 is about 271.9891323513.

Adding to 20121236 its reverse (63212102), we get a palindrome (83333338).

The spelling of 20121236 in words is "twenty million, one hundred twenty-one thousand, two hundred thirty-six".