20121535 has 16 divisors (see below), whose sum is σ = 27772416. Its totient is φ = 13709088.

The previous prime is 20121533. The next prime is 20121539. The reversal of 20121535 is 53512102.

It is a cyclic number.

It is not a de Polignac number, because 20121535 - 2¹ = 20121533 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121533) 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, 3942 + ... + 7468.

It is an arithmetic number, because the mean of its divisors is an integer number (1735776).

Almost surely, 2^20121535 is an apocalyptic number.

20121535 is a deficient number, since it is larger than the sum of its proper divisors (7650881).

20121535 is a wasteful number, since it uses less digits than its factorization.

20121535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3702.

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 20121535 is about 4485.7034008057. The cubic root of 20121535 is about 271.9904795904.

Adding to 20121535 its reverse (53512102), we get a palindrome (73633637).

It can be divided in two parts, 201 and 21535, that added together give a triangular number (21736 = T₂₀₈).

The spelling of 20121535 in words is "twenty million, one hundred twenty-one thousand, five hundred thirty-five".