105247821 has 64 divisors (see below), whose sum is σ = 178257920. Its totient is φ = 53887680.

The previous prime is 105247819. The next prime is 105247843. The reversal of 105247821 is 128742501.

It is not a de Polignac number, because 105247821 - 2¹ = 105247819 is a prime.

It is a super-2 number, since 2×105247821² = 22154207650496082, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (105247801) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 828660 + ... + 828786.

It is an arithmetic number, because the mean of its divisors is an integer number (2785280).

Almost surely, 2^105247821 is an apocalyptic number.

It is an amenable number.

105247821 is a deficient number, since it is larger than the sum of its proper divisors (73010099).

105247821 is a wasteful number, since it uses less digits than its factorization.

105247821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254.

The product of its (nonzero) digits is 4480, while the sum is 30.

The square root of 105247821 is about 10259.0360658300. The cubic root of 105247821 is about 472.1402631237.

The spelling of 105247821 in words is "one hundred five million, two hundred forty-seven thousand, eight hundred twenty-one".