18420901449 has 4 divisors (see below), whose sum is σ = 24561201936. Its totient is φ = 12280600964.

The previous prime is 18420901423. The next prime is 18420901453. The reversal of 18420901449 is 94410902481.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18420901449 - 2⁷ = 18420901321 is a prime.

It is a super-2 number, since 2×18420901449² (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 18420901449.

It is not an unprimeable number, because it can be changed into a prime (18420901049) 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, 3070150239 + ... + 3070150244.

It is an arithmetic number, because the mean of its divisors is an integer number (6140300484).

Almost surely, 2^18420901449 is an apocalyptic number.

It is an amenable number.

18420901449 is a deficient number, since it is larger than the sum of its proper divisors (6140300487).

18420901449 is an equidigital number, since it uses as much as digits as its factorization.

18420901449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6140300486.

The product of its (nonzero) digits is 82944, while the sum is 42.

The spelling of 18420901449 in words is "eighteen billion, four hundred twenty million, nine hundred one thousand, four hundred forty-nine".