20571057646 has 16 divisors (see below), whose sum is σ = 31385228400. Its totient is φ = 10109377728.

The previous prime is 20571057641. The next prime is 20571057649. The reversal of 20571057646 is 64675017502.

It is a super-3 number, since 3×20571057646³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20571057641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 839050 + ... + 863218.

It is an arithmetic number, because the mean of its divisors is an integer number (1961576775).

Almost surely, 2^20571057646 is an apocalyptic number.

20571057646 is a deficient number, since it is larger than the sum of its proper divisors (10814170754).

20571057646 is a wasteful number, since it uses less digits than its factorization.

20571057646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31443.

The product of its (nonzero) digits is 352800, while the sum is 43.

The spelling of 20571057646 in words is "twenty billion, five hundred seventy-one million, fifty-seven thousand, six hundred forty-six".