21507470376673 has 4 divisors (see below), whose sum is σ = 21507495500548. Its totient is φ = 21507445252800.

The previous prime is 21507470376671. The next prime is 21507470376677. The reversal of 21507470376673 is 37667307470512.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10453627504849 + 11053842871824 = 3233207^2 + 3324732^2 .

It is a cyclic number.

It is not a de Polignac number, because 21507470376673 - 2¹ = 21507470376671 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21507470376671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11230836 + ... + 13005637.

It is an arithmetic number, because the mean of its divisors is an integer number (5376873875137).

Almost surely, 2^{21507470376673} is an apocalyptic number.

It is an amenable number.

21507470376673 is a deficient number, since it is larger than the sum of its proper divisors (25123875).

21507470376673 is an equidigital number, since it uses as much as digits as its factorization.

21507470376673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25123874.

The product of its (nonzero) digits is 31116960, while the sum is 58.

The spelling of 21507470376673 in words is "twenty-one trillion, five hundred seven billion, four hundred seventy million, three hundred seventy-six thousand, six hundred seventy-three".