215520664355445 has 32 divisors (see below), whose sum is σ = 353263592707200. Its totient is φ = 112134494684160.

The previous prime is 215520664355441. The next prime is 215520664355461. The reversal of 215520664355445 is 544553466025512.

It is a happy number.

It is not a de Polignac number, because 215520664355445 - 2² = 215520664355441 is a prime.

It is a super-2 number, since 2×215520664355445² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215520664355441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 994281 + ... + 20785329.

It is an arithmetic number, because the mean of its divisors is an integer number (11039487272100).

Almost surely, 2^{215520664355445} is an apocalyptic number.

It is an amenable number.

215520664355445 is a deficient number, since it is larger than the sum of its proper divisors (137742928351755).

215520664355445 is a wasteful number, since it uses less digits than its factorization.

215520664355445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19808805.

The product of its (nonzero) digits is 86400000, while the sum is 57.

The spelling of 215520664355445 in words is "two hundred fifteen trillion, five hundred twenty billion, six hundred sixty-four million, three hundred fifty-five thousand, four hundred forty-five".