21550620007 has 4 divisors (see below), whose sum is σ = 24629280016. Its totient is φ = 18471960000.

The previous prime is 21550619999. The next prime is 21550620037. The reversal of 21550620007 is 70002605512.

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 21550620007 - 2³ = 21550619999 is a prime.

It is a super-2 number, since 2×21550620007² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21550620037) 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, 1539329994 + ... + 1539330007.

It is an arithmetic number, because the mean of its divisors is an integer number (6157320004).

Almost surely, 2^21550620007 is an apocalyptic number.

21550620007 is a deficient number, since it is larger than the sum of its proper divisors (3078660009).

21550620007 is an equidigital number, since it uses as much as digits as its factorization.

21550620007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3078660008.

The product of its (nonzero) digits is 4200, while the sum is 28.

The spelling of 21550620007 in words is "twenty-one billion, five hundred fifty million, six hundred twenty thousand, seven".