20021634137 has 4 divisors (see below), whose sum is σ = 20303629056. Its totient is φ = 19739639220.

The previous prime is 20021634131. The next prime is 20021634151. The reversal of 20021634137 is 73143612002.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 73143612002 = 2 ⋅36571806001.

It is a cyclic number.

It is not a de Polignac number, because 20021634137 - 2¹⁰ = 20021633113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20021634131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140997353 + ... + 140997494.

It is an arithmetic number, because the mean of its divisors is an integer number (5075907264).

Almost surely, 2^20021634137 is an apocalyptic number.

It is an amenable number.

20021634137 is a deficient number, since it is larger than the sum of its proper divisors (281994919).

20021634137 is an equidigital number, since it uses as much as digits as its factorization.

20021634137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281994918.

The product of its (nonzero) digits is 6048, while the sum is 29.

The spelling of 20021634137 in words is "twenty billion, twenty-one million, six hundred thirty-four thousand, one hundred thirty-seven".