2101639 has 8 divisors (see below), whose sum is σ = 2160000. Its totient is φ = 2044152.

The previous prime is 2101621. The next prime is 2101651. The reversal of 2101639 is 9361012.

2101639 = T₃₄ + T₃₅ + ... + T₂₃₂.

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 2101639 - 2⁵ = 2101607 is a prime.

It is a Duffinian number.

2101639 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2101669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10462 + ... + 10660.

It is an arithmetic number, because the mean of its divisors is an integer number (270000).

2^2101639 is an apocalyptic number.

2101639 is a deficient number, since it is larger than the sum of its proper divisors (58361).

2101639 is a wasteful number, since it uses less digits than its factorization.

2101639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 2101639 is about 1449.7030730463. The cubic root of 2101639 is about 128.0912232202.

It can be divided in two parts, 210 and 1639, that added together give a square (1849 = 43²).

The spelling of 2101639 in words is "two million, one hundred one thousand, six hundred thirty-nine".