21573730147 has 2 divisors, whose sum is σ = 21573730148. Its totient is φ = 21573730146.

The previous prime is 21573730121. The next prime is 21573730163. The reversal of 21573730147 is 74103737512.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21573730147 is a prime.

It is not a weakly prime, because it can be changed into another prime (21573730447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10786865073 + 10786865074.

It is an arithmetic number, because the mean of its divisors is an integer number (10786865074).

Almost surely, 2^21573730147 is an apocalyptic number.

21573730147 is a deficient number, since it is larger than the sum of its proper divisors (1).

21573730147 is an equidigital number, since it uses as much as digits as its factorization.

21573730147 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 123480, while the sum is 40.

The spelling of 21573730147 in words is "twenty-one billion, five hundred seventy-three million, seven hundred thirty thousand, one hundred forty-seven".