21506143273755 has 64 divisors (see below), whose sum is σ = 40144117432320. Its totient is φ = 9627997412736.

The previous prime is 21506143273691. The next prime is 21506143273763. The reversal of 21506143273755 is 55737234160512.

It is not a de Polignac number, because 21506143273755 - 2⁶ = 21506143273691 is a prime.

It is a super-2 number, since 2×21506143273755² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21506143273698 and 21506143273707.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4970587 + ... + 8229156.

It is an arithmetic number, because the mean of its divisors is an integer number (627251834880).

Almost surely, 2^{21506143273755} is an apocalyptic number.

21506143273755 is a deficient number, since it is larger than the sum of its proper divisors (18637974158565).

21506143273755 is a wasteful number, since it uses less digits than its factorization.

21506143273755 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13200080.

The product of its (nonzero) digits is 5292000, while the sum is 51.

The spelling of 21506143273755 in words is "twenty-one trillion, five hundred six billion, one hundred forty-three million, two hundred seventy-three thousand, seven hundred fifty-five".