2861639 has 8 divisors (see below), whose sum is σ = 3143568. Its totient is φ = 2583360.

The previous prime is 2861623. The next prime is 2861657. The reversal of 2861639 is 9361682.

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 2861639 - 2⁴ = 2861623 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2861599 and 2861608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2861659) 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, 899 + ... + 2555.

It is an arithmetic number, because the mean of its divisors is an integer number (392946).

2^2861639 is an apocalyptic number.

2861639 is a deficient number, since it is larger than the sum of its proper divisors (281929).

2861639 is a wasteful number, since it uses less digits than its factorization.

2861639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1825.

The product of its digits is 15552, while the sum is 35.

The square root of 2861639 is about 1691.6379636317. The cubic root of 2861639 is about 141.9727349623.

The spelling of 2861639 in words is "two million, eight hundred sixty-one thousand, six hundred thirty-nine".