105720639 has 16 divisors (see below), whose sum is σ = 142884864. Its totient is φ = 69524000.

The previous prime is 105720613. The next prime is 105720649. The reversal of 105720639 is 936027501.

It is a cyclic number.

It is not a de Polignac number, because 105720639 - 2⁸ = 105720383 is a prime.

It is a super-2 number, since 2×105720639² = 22353707021136642, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (105720649) 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, 115594 + ... + 116504.

It is an arithmetic number, because the mean of its divisors is an integer number (8930304).

Almost surely, 2^105720639 is an apocalyptic number.

105720639 is a deficient number, since it is larger than the sum of its proper divisors (37164225).

105720639 is a wasteful number, since it uses less digits than its factorization.

105720639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1398.

The product of its (nonzero) digits is 11340, while the sum is 33.

The square root of 105720639 is about 10282.0542208257. The cubic root of 105720639 is about 472.8462253426.

The spelling of 105720639 in words is "one hundred five million, seven hundred twenty thousand, six hundred thirty-nine".