51661610510161 has 8 divisors (see below), whose sum is σ = 52079285543400. Its totient is φ = 51244881514752.

The previous prime is 51661610510149. The next prime is 51661610510173. The reversal of 51661610510161 is 16101501616615.

It is an interprime number because it is at equal distance from previous prime (51661610510149) and next prime (51661610510173).

It can be written as a sum of positive squares in 4 ways, for example, as 10269179157136 + 41392431353025 = 3204556^2 + 6433695^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 51661610510161 - 2¹⁷ = 51661610379089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51661610510141) 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, 236399800 + ... + 236618233.

It is an arithmetic number, because the mean of its divisors is an integer number (6509910692925).

Almost surely, 2^{51661610510161} is an apocalyptic number.

It is an amenable number.

51661610510161 is a deficient number, since it is larger than the sum of its proper divisors (417675033239).

51661610510161 is a wasteful number, since it uses less digits than its factorization.

51661610510161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473018915.

The product of its (nonzero) digits is 32400, while the sum is 40.

The spelling of 51661610510161 in words is "fifty-one trillion, six hundred sixty-one billion, six hundred ten million, five hundred ten thousand, one hundred sixty-one".