1655221651215 has 16 divisors (see below), whose sum is σ = 2889114155136. Its totient is φ = 802531709600.

The previous prime is 1655221651201. The next prime is 1655221651243. The reversal of 1655221651215 is 5121561225561.

It is a happy number.

It is not a de Polignac number, because 1655221651215 - 2⁶ = 1655221651151 is a prime.

It is a super-2 number, since 2×1655221651215² (a number of 25 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5015823021 + ... + 5015823350.

It is an arithmetic number, because the mean of its divisors is an integer number (180569634696).

Almost surely, 2^{1655221651215} is an apocalyptic number.

1655221651215 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1655221651215 is a deficient number, since it is larger than the sum of its proper divisors (1233892503921).

1655221651215 is a wasteful number, since it uses less digits than its factorization.

1655221651215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10031646390.

The product of its digits is 180000, while the sum is 42.

Adding to 1655221651215 its reverse (5121561225561), we get a palindrome (6776782876776).

The spelling of 1655221651215 in words is "one trillion, six hundred fifty-five billion, two hundred twenty-one million, six hundred fifty-one thousand, two hundred fifteen".