161611166101551 has 16 divisors (see below), whose sum is σ = 215504394513408. Its totient is φ = 107729358105600.

The previous prime is 161611166101487. The next prime is 161611166101571. The reversal of 161611166101551 is 155101661116161.

It is not a de Polignac number, because 161611166101551 - 2⁶ = 161611166101487 is a prime.

It is a super-2 number, since 2×161611166101551² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161611166101571) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2539147810 + ... + 2539211456.

It is an arithmetic number, because the mean of its divisors is an integer number (13469024657088).

Almost surely, 2^{161611166101551} is an apocalyptic number.

161611166101551 is a deficient number, since it is larger than the sum of its proper divisors (53893228411857).

161611166101551 is a wasteful number, since it uses less digits than its factorization.

161611166101551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140062.

The product of its (nonzero) digits is 32400, while the sum is 42.

The spelling of 161611166101551 in words is "one hundred sixty-one trillion, six hundred eleven billion, one hundred sixty-six million, one hundred one thousand, five hundred fifty-one".