20121142157 has 2 divisors, whose sum is σ = 20121142158. Its totient is φ = 20121142156.

The previous prime is 20121142121. The next prime is 20121142207. The reversal of 20121142157 is 75124112102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18855134596 + 1266007561 = 137314^2 + 35581^2 .

It is a cyclic number.

It is not a de Polignac number, because 20121142157 - 2¹⁶ = 20121076621 is a prime.

It is a super-3 number, since 3×20121142157³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20121142957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060571078 + 10060571079.

It is an arithmetic number, because the mean of its divisors is an integer number (10060571079).

Almost surely, 2^20121142157 is an apocalyptic number.

It is an amenable number.

20121142157 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121142157 is an equidigital number, since it uses as much as digits as its factorization.

20121142157 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1120, while the sum is 26.

Adding to 20121142157 its reverse (75124112102), we get a palindrome (95245254259).

The spelling of 20121142157 in words is "twenty billion, one hundred twenty-one million, one hundred forty-two thousand, one hundred fifty-seven".