2618639920 has 80 divisors (see below), whose sum is σ = 6604889760. Its totient is φ = 959772672.

The previous prime is 2618639917. The next prime is 2618639923. The reversal of 2618639920 is 299368162.

It is an interprime number because it is at equal distance from previous prime (2618639917) and next prime (2618639923).

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (2618639923) 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, 133291 + ... + 151669.

It is an arithmetic number, because the mean of its divisors is an integer number (82561122).

Almost surely, 2^2618639920 is an apocalyptic number.

2618639920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2618639920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3302444880).

2618639920 is an abundant number, since it is smaller than the sum of its proper divisors (3986249840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2618639920 is a wasteful number, since it uses less digits than its factorization.

2618639920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18542 (or 18536 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 46.

The square root of 2618639920 is about 51172.6481628614. The cubic root of 2618639920 is about 1378.3470933312.

The spelling of 2618639920 in words is "two billion, six hundred eighteen million, six hundred thirty-nine thousand, nine hundred twenty".