2151780617267 has 4 divisors (see below), whose sum is σ = 2151786651120. Its totient is φ = 2151774583416.

The previous prime is 2151780617257. The next prime is 2151780617281. The reversal of 2151780617267 is 7627160871512.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2151780617267 - 2⁴ = 2151780617251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2151780617257) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2445983 + ... + 3207240.

It is an arithmetic number, because the mean of its divisors is an integer number (537946662780).

Almost surely, 2^{2151780617267} is an apocalyptic number.

2151780617267 is a deficient number, since it is larger than the sum of its proper divisors (6033853).

2151780617267 is an equidigital number, since it uses as much as digits as its factorization.

2151780617267 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6033852.

The product of its (nonzero) digits is 1975680, while the sum is 53.

The spelling of 2151780617267 in words is "two trillion, one hundred fifty-one billion, seven hundred eighty million, six hundred seventeen thousand, two hundred sixty-seven".