20457474891 has 16 divisors (see below), whose sum is σ = 31494672384. Its totient is φ = 11569469184.

The previous prime is 20457474889. The next prime is 20457474907. The reversal of 20457474891 is 19847475402.

It is not a de Polignac number, because 20457474891 - 2¹ = 20457474889 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20457474811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5019435 + ... + 5023508.

It is an arithmetic number, because the mean of its divisors is an integer number (1968417024).

Almost surely, 2^20457474891 is an apocalyptic number.

20457474891 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20457474891 is a deficient number, since it is larger than the sum of its proper divisors (11037197493).

20457474891 is a wasteful number, since it uses less digits than its factorization.

20457474891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10043050.

The product of its (nonzero) digits is 2257920, while the sum is 51.

The spelling of 20457474891 in words is "twenty billion, four hundred fifty-seven million, four hundred seventy-four thousand, eight hundred ninety-one".