21506142744715 has 8 divisors (see below), whose sum is σ = 26192555940240. Its totient is φ = 16948124431392.

The previous prime is 21506142744689. The next prime is 21506142744781. The reversal of 21506142744715 is 51744724160512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21506142744715 - 2⁷ = 21506142744587 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32098720180 + ... + 32098720849.

It is an arithmetic number, because the mean of its divisors is an integer number (3274069492530).

Almost surely, 2^{21506142744715} is an apocalyptic number.

21506142744715 is a deficient number, since it is larger than the sum of its proper divisors (4686413195525).

21506142744715 is an equidigital number, since it uses as much as digits as its factorization.

21506142744715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64197441101.

The product of its (nonzero) digits is 1881600, while the sum is 49.

The spelling of 21506142744715 in words is "twenty-one trillion, five hundred six billion, one hundred forty-two million, seven hundred forty-four thousand, seven hundred fifteen".