2621979887 has 4 divisors (see below), whose sum is σ = 2776214016. Its totient is φ = 2467745760.

The previous prime is 2621979859. The next prime is 2621979947. The reversal of 2621979887 is 7889791262.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7889791262 = 2 ⋅3944895631.

It is a cyclic number.

It is not a de Polignac number, because 2621979887 - 2⁶ = 2621979823 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2621979827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77117039 + ... + 77117072.

It is an arithmetic number, because the mean of its divisors is an integer number (694053504).

Almost surely, 2^2621979887 is an apocalyptic number.

2621979887 is a deficient number, since it is larger than the sum of its proper divisors (154234129).

2621979887 is a wasteful number, since it uses less digits than its factorization.

2621979887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154234128.

The product of its digits is 6096384, while the sum is 59.

The square root of 2621979887 is about 51205.2720625523. The cubic root of 2621979887 is about 1378.9328526165.

The spelling of 2621979887 in words is "two billion, six hundred twenty-one million, nine hundred seventy-nine thousand, eight hundred eighty-seven".