20447142751 has 24 divisors (see below), whose sum is σ = 24859288160. Its totient is φ = 16471475712.

The previous prime is 20447142743. The next prime is 20447142769. The reversal of 20447142751 is 15724174402.

It is not a de Polignac number, because 20447142751 - 2³ = 20447142743 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20447142751.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20447142731) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1475965 + ... + 1489753.

Almost surely, 2^20447142751 is an apocalyptic number.

20447142751 is a deficient number, since it is larger than the sum of its proper divisors (4412145409).

20447142751 is a wasteful number, since it uses less digits than its factorization.

20447142751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14563 (or 14546 counting only the distinct ones).

The product of its (nonzero) digits is 62720, while the sum is 37.

The spelling of 20447142751 in words is "twenty billion, four hundred forty-seven million, one hundred forty-two thousand, seven hundred fifty-one".