1811196931551 has 16 divisors (see below), whose sum is σ = 2760587042304. Its totient is φ = 1034719209504.

The previous prime is 1811196931499. The next prime is 1811196931619. The reversal of 1811196931551 is 1551396911181.

It is not a de Polignac number, because 1811196931551 - 2⁹ = 1811196931039 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1811196931494 and 1811196931503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1811196931151) 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, 10347211 + ... + 10520796.

It is an arithmetic number, because the mean of its divisors is an integer number (172536690144).

Almost surely, 2^{1811196931551} is an apocalyptic number.

1811196931551 is a deficient number, since it is larger than the sum of its proper divisors (949390110753).

1811196931551 is a wasteful number, since it uses less digits than its factorization.

1811196931551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20872150.

The product of its digits is 291600, while the sum is 51.

The spelling of 1811196931551 in words is "one trillion, eight hundred eleven billion, one hundred ninety-six million, nine hundred thirty-one thousand, five hundred fifty-one".