20121003 has 24 divisors (see below), whose sum is σ = 33364448. Its totient is φ = 11446272.

The previous prime is 20120999. The next prime is 20121043. The reversal of 20121003 is 30012102.

It is a happy number.

It is not a de Polignac number, because 20121003 - 2² = 20120999 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20121043) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16875 + ... + 18027.

Almost surely, 2^20121003 is an apocalyptic number.

20121003 is a deficient number, since it is larger than the sum of its proper divisors (13243445).

20121003 is a wasteful number, since it uses less digits than its factorization.

20121003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1443 (or 1440 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 20121003 is about 4485.6441009068. The cubic root of 20121003 is about 271.9880824868.

Adding to 20121003 its reverse (30012102), we get a palindrome (50133105).

The spelling of 20121003 in words is "twenty million, one hundred twenty-one thousand, three".