21656156106 has 32 divisors (see below), whose sum is σ = 46659553920. Its totient is φ = 6661214784.

The previous prime is 21656156063. The next prime is 21656156117. The reversal of 21656156106 is 60165165612.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 197851 + ... + 287153.

It is an arithmetic number, because the mean of its divisors is an integer number (1458111060).

Almost surely, 2^21656156106 is an apocalyptic number.

21656156106 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21656156106 is an abundant number, since it is smaller than the sum of its proper divisors (25003397814).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21656156106 is a wasteful number, since it uses less digits than its factorization.

21656156106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92430.

The product of its (nonzero) digits is 64800, while the sum is 39.

The spelling of 21656156106 in words is "twenty-one billion, six hundred fifty-six million, one hundred fifty-six thousand, one hundred six".