15869021156836 has 9 divisors (see below), whose sum is σ = 27770800967049. Its totient is φ = 7934506594824.

The previous prime is 15869021156819. The next prime is 15869021156839. The reversal of 15869021156836 is 63865112096851.

It is a happy number.

The square root of 15869021156836 is 3983594.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 14785639944100 + 1083381212736 = 3845210^2 + 1040856^2 .

It is a super-2 number, since 2×15869021156836² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15869021156839) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 6971290 + ... + 8963086.

Almost surely, 2^{15869021156836} is an apocalyptic number.

15869021156836 is the 3983594-th square number.

It is an amenable number.

15869021156836 is a deficient number, since it is larger than the sum of its proper divisors (11901779810213).

15869021156836 is an frugal number, since it uses more digits than its factorization.

15869021156836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3983598 (or 1991799 counting only the distinct ones).

The product of its (nonzero) digits is 18662400, while the sum is 61.

The spelling of 15869021156836 in words is "fifteen trillion, eight hundred sixty-nine billion, twenty-one million, one hundred fifty-six thousand, eight hundred thirty-six".