20700121 has 16 divisors (see below), whose sum is σ = 23200128. Its totient is φ = 18345600.

The previous prime is 20700109. The next prime is 20700143. The reversal of 20700121 is 12100702.

It is not a de Polignac number, because 20700121 - 2⁷ = 20699993 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20700181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37570 + ... + 38116.

It is an arithmetic number, because the mean of its divisors is an integer number (1450008).

Almost surely, 2^20700121 is an apocalyptic number.

It is an amenable number.

20700121 is a deficient number, since it is larger than the sum of its proper divisors (2500007).

20700121 is a wasteful number, since it uses less digits than its factorization.

20700121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 672.

The product of its (nonzero) digits is 28, while the sum is 13.

The square root of 20700121 is about 4549.7385639177. The cubic root of 20700121 is about 274.5728730227.

Adding to 20700121 its reverse (12100702), we get a palindrome (32800823).

The spelling of 20700121 in words is "twenty million, seven hundred thousand, one hundred twenty-one".