21620751007 has 2 divisors, whose sum is σ = 21620751008. Its totient is φ = 21620751006.

The previous prime is 21620750981. The next prime is 21620751041. The reversal of 21620751007 is 70015702612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21620751007 - 2¹⁵ = 21620718239 is a prime.

It is a super-3 number, since 3×21620751007³ (a number of 32 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21620751007.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21620751707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10810375503 + 10810375504.

It is an arithmetic number, because the mean of its divisors is an integer number (10810375504).

Almost surely, 2^21620751007 is an apocalyptic number.

21620751007 is a deficient number, since it is larger than the sum of its proper divisors (1).

21620751007 is an equidigital number, since it uses as much as digits as its factorization.

21620751007 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5880, while the sum is 31.

The spelling of 21620751007 in words is "twenty-one billion, six hundred twenty million, seven hundred fifty-one thousand, seven".