102021405 has 16 divisors (see below), whose sum is σ = 163616640. Its totient is φ = 54283968.

The previous prime is 102021389. The next prime is 102021419. The reversal of 102021405 is 504120201.

It is not a de Polignac number, because 102021405 - 2⁴ = 102021389 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1162 + ... + 14331.

It is an arithmetic number, because the mean of its divisors is an integer number (10226040).

Almost surely, 2^102021405 is an apocalyptic number.

102021405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

102021405 is a deficient number, since it is larger than the sum of its proper divisors (61595235).

102021405 is a wasteful number, since it uses less digits than its factorization.

102021405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15940.

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 102021405 is about 10100.5645881802. The cubic root of 102021405 is about 467.2655539471.

Adding to 102021405 its reverse (504120201), we get a palindrome (606141606).

The spelling of 102021405 in words is "one hundred two million, twenty-one thousand, four hundred five".