20847091839390 has 40 divisors (see below), whose sum is σ = 56055513614760. Its totient is φ = 5559224490288.

The previous prime is 20847091839323. The next prime is 20847091839397. The reversal of 20847091839390 is 9393819074802.

20847091839390 is a `hidden beast` number, since 2 + 0 + 8 + 4 + 70 + 91 + 8 + 393 + 90 = 666.

It is a super-2 number, since 2×20847091839390² (a number of 27 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20847091839397) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 12868574400 + ... + 12868576019.

It is an arithmetic number, because the mean of its divisors is an integer number (1401387840369).

Almost surely, 2^{20847091839390} is an apocalyptic number.

20847091839390 is an abundant number, since it is smaller than the sum of its proper divisors (35208421775370).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20847091839390 is a wasteful number, since it uses less digits than its factorization.

20847091839390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25737150438 (or 25737150429 counting only the distinct ones).

The product of its (nonzero) digits is 23514624, while the sum is 63.

The spelling of 20847091839390 in words is "twenty trillion, eight hundred forty-seven billion, ninety-one million, eight hundred thirty-nine thousand, three hundred ninety".