21433340987 has 2 divisors, whose sum is σ = 21433340988. Its totient is φ = 21433340986.

The previous prime is 21433340983. The next prime is 21433341031. The reversal of 21433340987 is 78904333412.

It is an a-pointer prime, because the next prime (21433341031) can be obtained adding 21433340987 to its sum of digits (44).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21433340987 - 2² = 21433340983 is a prime.

It is not a weakly prime, because it can be changed into another prime (21433340983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10716670493 + 10716670494.

It is an arithmetic number, because the mean of its divisors is an integer number (10716670494).

Almost surely, 2^21433340987 is an apocalyptic number.

21433340987 is a deficient number, since it is larger than the sum of its proper divisors (1).

21433340987 is an equidigital number, since it uses as much as digits as its factorization.

21433340987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 435456, while the sum is 44.

The spelling of 21433340987 in words is "twenty-one billion, four hundred thirty-three million, three hundred forty thousand, nine hundred eighty-seven".