1971776678551 has 8 divisors (see below), whose sum is σ = 2024428334544. Its totient is φ = 1919342143680.

The previous prime is 1971776678539. The next prime is 1971776678567. The reversal of 1971776678551 is 1558766771791.

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 1971776678551 - 2¹¹ = 1971776676503 is a prime.

It is a super-2 number, since 2×1971776678551² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1971776618551) 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, 54261876 + ... + 54298201.

It is an arithmetic number, because the mean of its divisors is an integer number (253053541818).

Almost surely, 2^{1971776678551} is an apocalyptic number.

1971776678551 is a deficient number, since it is larger than the sum of its proper divisors (52651655993).

1971776678551 is a wasteful number, since it uses less digits than its factorization.

1971776678551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108560561.

The product of its digits is 155584800, while the sum is 70.

The spelling of 1971776678551 in words is "one trillion, nine hundred seventy-one billion, seven hundred seventy-six million, six hundred seventy-eight thousand, five hundred fifty-one".