20100657761 has 12 divisors (see below), whose sum is σ = 21361213500. Its totient is φ = 18910636800.

The previous prime is 20100657737. The next prime is 20100657781. The reversal of 20100657761 is 16775600102.

It can be written as a sum of positive squares in 6 ways, for example, as 460317025 + 19640340736 = 21455^2 + 140144^2 .

It is not a de Polignac number, because 20100657761 - 2³⁰ = 19026915937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20100657781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 781811 + ... + 807111.

It is an arithmetic number, because the mean of its divisors is an integer number (1780101125).

Almost surely, 2^20100657761 is an apocalyptic number.

It is an amenable number.

20100657761 is a deficient number, since it is larger than the sum of its proper divisors (1260555739).

20100657761 is a wasteful number, since it uses less digits than its factorization.

20100657761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28084 (or 28067 counting only the distinct ones).

The product of its (nonzero) digits is 17640, while the sum is 35.

The spelling of 20100657761 in words is "twenty billion, one hundred million, six hundred fifty-seven thousand, seven hundred sixty-one".