20897934019 has 4 divisors (see below), whose sum is σ = 21013392400. Its totient is φ = 20782475640.

The previous prime is 20897934017. The next prime is 20897934047. The reversal of 20897934019 is 91043979802.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20897934019 - 2¹ = 20897934017 is a prime.

It is a super-2 number, since 2×20897934019² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20897934017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57728919 + ... + 57729280.

It is an arithmetic number, because the mean of its divisors is an integer number (5253348100).

Almost surely, 2^20897934019 is an apocalyptic number.

20897934019 is a deficient number, since it is larger than the sum of its proper divisors (115458381).

20897934019 is a wasteful number, since it uses less digits than its factorization.

20897934019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115458380.

The product of its (nonzero) digits is 979776, while the sum is 52.

The spelling of 20897934019 in words is "twenty billion, eight hundred ninety-seven million, nine hundred thirty-four thousand, nineteen".