20992906237 has 4 divisors (see below), whose sum is σ = 20998361376. Its totient is φ = 20987451100.

The previous prime is 20992906211. The next prime is 20992906279. The reversal of 20992906237 is 73260929902.

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.

It is a cyclic number.

It is not a de Polignac number, because 20992906237 - 2¹⁵ = 20992873469 is a prime.

It is a super-2 number, since 2×20992906237² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20992906537) 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, 2721793 + ... + 2729494.

It is an arithmetic number, because the mean of its divisors is an integer number (5249590344).

Almost surely, 2^20992906237 is an apocalyptic number.

It is an amenable number.

20992906237 is a deficient number, since it is larger than the sum of its proper divisors (5455139).

20992906237 is an equidigital number, since it uses as much as digits as its factorization.

20992906237 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5455138.

The product of its (nonzero) digits is 734832, while the sum is 49.

The spelling of 20992906237 in words is "twenty billion, nine hundred ninety-two million, nine hundred six thousand, two hundred thirty-seven".