20651256471 has 8 divisors (see below), whose sum is σ = 27561514240. Its totient is φ = 13754251512.

The previous prime is 20651256443. The next prime is 20651256487. The reversal of 20651256471 is 17465215602.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20651256471 - 2⁷ = 20651256343 is a prime.

It is a super-3 number, since 3×20651256471³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20651256401) 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 7 ways as a sum of consecutive naturals, for example, 3309565 + ... + 3315798.

It is an arithmetic number, because the mean of its divisors is an integer number (3445189280).

Almost surely, 2^20651256471 is an apocalyptic number.

20651256471 is a deficient number, since it is larger than the sum of its proper divisors (6910257769).

20651256471 is a wasteful number, since it uses less digits than its factorization.

20651256471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6626405.

The product of its (nonzero) digits is 100800, while the sum is 39.

The spelling of 20651256471 in words is "twenty billion, six hundred fifty-one million, two hundred fifty-six thousand, four hundred seventy-one".