20013121000 has 32 divisors (see below), whose sum is σ = 46830705480. Its totient is φ = 8005248000.

The previous prime is 20013120997. The next prime is 20013121003. The reversal of 20013121000 is 12131002.

It is an interprime number because it is at equal distance from previous prime (20013120997) and next prime (20013121003).

It can be written as a sum of positive squares in 4 ways, for example, as 1625218596 + 18387902404 = 40314^2 + 135602^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is not an unprimeable number, because it can be changed into a prime (20013121003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10005561 + ... + 10007560.

Almost surely, 2^20013121000 is an apocalyptic number.

20013121000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20013121000 is an abundant number, since it is smaller than the sum of its proper divisors (26817584480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20013121000 is a wasteful number, since it uses less digits than its factorization.

20013121000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20013142 (or 20013128 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 10.

Adding to 20013121000 its reverse (12131002), we get a palindrome (20025252002).

The spelling of 20013121000 in words is "twenty billion, thirteen million, one hundred twenty-one thousand".