205929670781 has 8 divisors (see below), whose sum is σ = 214888769664. Its totient is φ = 196971041520.

The previous prime is 205929670763. The next prime is 205929670801. The reversal of 205929670781 is 187076929502.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205929670781 is a prime.

It is a super-2 number, since 2×205929670781² (a number of 23 digits) contains 22 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 (205929670721) 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, 1008515 + ... + 1195391.

It is an arithmetic number, because the mean of its divisors is an integer number (26861096208).

Almost surely, 2^205929670781 is an apocalyptic number.

It is an amenable number.

205929670781 is a deficient number, since it is larger than the sum of its proper divisors (8959098883).

205929670781 is a wasteful number, since it uses less digits than its factorization.

205929670781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234811.

The product of its (nonzero) digits is 3810240, while the sum is 56.

The spelling of 205929670781 in words is "two hundred five billion, nine hundred twenty-nine million, six hundred seventy thousand, seven hundred eighty-one".