21155656650157 has 32 divisors (see below), whose sum is σ = 21525076007424. Its totient is φ = 20790771302400.

The previous prime is 21155656650143. The next prime is 21155656650209. The reversal of 21155656650157 is 75105665655112.

It is a cyclic number.

It is not a de Polignac number, because 21155656650157 - 2⁴³ = 12359563627949 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21155656650098 and 21155656650107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21155656650127) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4044282732 + ... + 4044287962.

It is an arithmetic number, because the mean of its divisors is an integer number (672658625232).

Almost surely, 2^{21155656650157} is an apocalyptic number.

It is an amenable number.

21155656650157 is a deficient number, since it is larger than the sum of its proper divisors (369419357267).

21155656650157 is a wasteful number, since it uses less digits than its factorization.

21155656650157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6309.

The product of its (nonzero) digits is 9450000, while the sum is 55.

The spelling of 21155656650157 in words is "twenty-one trillion, one hundred fifty-five billion, six hundred fifty-six million, six hundred fifty thousand, one hundred fifty-seven".