2151666556663 has 8 divisors (see below), whose sum is σ = 2318350280400. Its totient is φ = 1985150106048.

The previous prime is 2151666556661. The next prime is 2151666556667. The reversal of 2151666556663 is 3666556661512.

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 2151666556663 - 2¹ = 2151666556661 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2151666556598 and 2151666556607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2151666556661) 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, 41791558 + ... + 41843011.

It is an arithmetic number, because the mean of its divisors is an integer number (289793785050).

Almost surely, 2^{2151666556663} is an apocalyptic number.

2151666556663 is a deficient number, since it is larger than the sum of its proper divisors (166683723737).

2151666556663 is a wasteful number, since it uses less digits than its factorization.

2151666556663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83636561.

The product of its digits is 34992000, while the sum is 58.

The spelling of 2151666556663 in words is "two trillion, one hundred fifty-one billion, six hundred sixty-six million, five hundred fifty-six thousand, six hundred sixty-three".