21507834419 has 2 divisors, whose sum is σ = 21507834420. Its totient is φ = 21507834418.

The previous prime is 21507834401. The next prime is 21507834431. The reversal of 21507834419 is 91443870512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21507834419 - 2⁸ = 21507834163 is a prime.

It is a super-2 number, since 2×21507834419² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21507834419.

It is not a weakly prime, because it can be changed into another prime (21507804419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10753917209 + 10753917210.

It is an arithmetic number, because the mean of its divisors is an integer number (10753917210).

Almost surely, 2^21507834419 is an apocalyptic number.

21507834419 is a deficient number, since it is larger than the sum of its proper divisors (1).

21507834419 is an equidigital number, since it uses as much as digits as its factorization.

21507834419 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 241920, while the sum is 44.

The spelling of 21507834419 in words is "twenty-one billion, five hundred seven million, eight hundred thirty-four thousand, four hundred nineteen".