205101251620 has 24 divisors (see below), whose sum is σ = 430721182584. Its totient is φ = 82038871296.

The previous prime is 205101251609. The next prime is 205101251669. The reversal of 205101251620 is 26152101502.

It can be written as a sum of positive squares in 4 ways, for example, as 62696153664 + 142405097956 = 250392^2 + 377366^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1765654 + ... + 1878226.

It is an arithmetic number, because the mean of its divisors is an integer number (17946715941).

Almost surely, 2^205101251620 is an apocalyptic number.

205101251620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205101251620 is an abundant number, since it is smaller than the sum of its proper divisors (225619930964).

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

205101251620 is a wasteful number, since it uses less digits than its factorization.

205101251620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203679 (or 203677 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 25.

The spelling of 205101251620 in words is "two hundred five billion, one hundred one million, two hundred fifty-one thousand, six hundred twenty".