21201201019 has 4 divisors (see below), whose sum is σ = 21202074760. Its totient is φ = 21200327280.

The previous prime is 21201200987. The next prime is 21201201061. The reversal of 21201201019 is 91010210212.

It is a happy number.

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 21201201019 - 2⁵ = 21201200987 is a prime.

It is a super-2 number, since 2×21201201019² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21201200987 and 21201201005.

It is not an unprimeable number, because it can be changed into a prime (21201261019) 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, 399402 + ... + 449359.

It is an arithmetic number, because the mean of its divisors is an integer number (5300518690).

Almost surely, 2^21201201019 is an apocalyptic number.

21201201019 is a deficient number, since it is larger than the sum of its proper divisors (873741).

21201201019 is an equidigital number, since it uses as much as digits as its factorization.

21201201019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 873740.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 21201201019 in words is "twenty-one billion, two hundred one million, two hundred one thousand, nineteen".