161210956251 has 16 divisors (see below), whose sum is σ = 221047228800. Its totient is φ = 104465262528.

The previous prime is 161210956241. The next prime is 161210956261. The reversal of 161210956251 is 152659012161.

It is an interprime number because it is at equal distance from previous prime (161210956241) and next prime (161210956261).

It is not a de Polignac number, because 161210956251 - 2⁹ = 161210955739 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161210956201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5101081 + ... + 5132586.

It is an arithmetic number, because the mean of its divisors is an integer number (13815451800).

Almost surely, 2^161210956251 is an apocalyptic number.

161210956251 is a deficient number, since it is larger than the sum of its proper divisors (59836272549).

161210956251 is a wasteful number, since it uses less digits than its factorization.

161210956251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10233818.

The product of its (nonzero) digits is 32400, while the sum is 39.

The spelling of 161210956251 in words is "one hundred sixty-one billion, two hundred ten million, nine hundred fifty-six thousand, two hundred fifty-one".