20015121 has 16 divisors (see below), whose sum is σ = 30844800. Its totient is φ = 11307648.

The previous prime is 20015087. The next prime is 20015131. The reversal of 20015121 is 12151002.

It is not a de Polignac number, because 20015121 - 2⁷ = 20014993 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20015097 and 20015106.

It is not an unprimeable number, because it can be changed into a prime (20015131) 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, 3486 + ... + 7223.

It is an arithmetic number, because the mean of its divisors is an integer number (1927800).

Almost surely, 2^20015121 is an apocalyptic number.

20015121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20015121 is a deficient number, since it is larger than the sum of its proper divisors (10829679).

20015121 is a wasteful number, since it uses less digits than its factorization.

20015121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10808.

The product of its (nonzero) digits is 20, while the sum is 12.

The square root of 20015121 is about 4473.8262147741. The cubic root of 20015121 is about 271.5101522748.

Adding to 20015121 its reverse (12151002), we get a palindrome (32166123).

The spelling of 20015121 in words is "twenty million, fifteen thousand, one hundred twenty-one".