20199999879929 has 2 divisors, whose sum is σ = 20199999879930. Its totient is φ = 20199999879928.

The previous prime is 20199999879841. The next prime is 20199999879947. The reversal of 20199999879929 is 92997899999102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20159633042704 + 40366837225 = 4489948^2 + 200915^2 .

It is a cyclic number.

It is not a de Polignac number, because 20199999879929 - 2¹² = 20199999875833 is a prime.

It is a super-2 number, since 2×20199999879929² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20199999872929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10099999939964 + 10099999939965.

It is an arithmetic number, because the mean of its divisors is an integer number (10099999939965).

Almost surely, 2^{20199999879929} is an apocalyptic number.

It is an amenable number.

20199999879929 is a deficient number, since it is larger than the sum of its proper divisors (1).

20199999879929 is an equidigital number, since it uses as much as digits as its factorization.

20199999879929 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9642465504, while the sum is 92.

The spelling of 20199999879929 in words is "twenty trillion, one hundred ninety-nine billion, nine hundred ninety-nine million, eight hundred seventy-nine thousand, nine hundred twenty-nine".