21573730151 has 4 divisors (see below), whose sum is σ = 21635902632. Its totient is φ = 21511557672.

The previous prime is 21573730147. The next prime is 21573730163. The reversal of 21573730151 is 15103737512.

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

It is a cyclic number.

It is not a de Polignac number, because 21573730151 - 2² = 21573730147 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21573730121) 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, 31085720 + ... + 31086413.

It is an arithmetic number, because the mean of its divisors is an integer number (5408975658).

Almost surely, 2^21573730151 is an apocalyptic number.

21573730151 is a deficient number, since it is larger than the sum of its proper divisors (62172481).

21573730151 is an equidigital number, since it uses as much as digits as its factorization.

21573730151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62172480.

The product of its (nonzero) digits is 22050, while the sum is 35.

The spelling of 21573730151 in words is "twenty-one billion, five hundred seventy-three million, seven hundred thirty thousand, one hundred fifty-one".