20121021139 has 2 divisors, whose sum is σ = 20121021140. Its totient is φ = 20121021138.

The previous prime is 20121021101. The next prime is 20121021149. The reversal of 20121021139 is 93112012102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20121021139 - 2⁹ = 20121020627 is a prime.

It is not a weakly prime, because it can be changed into another prime (20121021149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060510569 + 10060510570.

It is an arithmetic number, because the mean of its divisors is an integer number (10060510570).

Almost surely, 2^20121021139 is an apocalyptic number.

20121021139 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121021139 is an equidigital number, since it uses as much as digits as its factorization.

20121021139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 22.

The spelling of 20121021139 in words is "twenty billion, one hundred twenty-one million, twenty-one thousand, one hundred thirty-nine".