20616631199 has 4 divisors (see below), whose sum is σ = 20617542936. Its totient is φ = 20615719464.

The previous prime is 20616631157. The next prime is 20616631219. The reversal of 20616631199 is 99113661602.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99113661602 = 2 ⋅49556830801.

It is a cyclic number.

It is not a de Polignac number, because 20616631199 - 2²⁸ = 20348195743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20616631109) 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, 421064 + ... + 467469.

It is an arithmetic number, because the mean of its divisors is an integer number (5154385734).

Almost surely, 2^20616631199 is an apocalyptic number.

20616631199 is a deficient number, since it is larger than the sum of its proper divisors (911737).

20616631199 is an equidigital number, since it uses as much as digits as its factorization.

20616631199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 911736.

The product of its (nonzero) digits is 104976, while the sum is 44.

The spelling of 20616631199 in words is "twenty billion, six hundred sixteen million, six hundred thirty-one thousand, one hundred ninety-nine".