19800155002 has 4 divisors (see below), whose sum is σ = 29700232506. Its totient is φ = 9900077500.

The previous prime is 19800154993. The next prime is 19800155027. The reversal of 19800155002 is 20055100891.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 13770787801 + 6029367201 = 117349^2 + 77649^2 .

It is a super-2 number, since 2×19800155002² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4950038749 + ... + 4950038752.

Almost surely, 2^19800155002 is an apocalyptic number.

19800155002 is a deficient number, since it is larger than the sum of its proper divisors (9900077504).

19800155002 is an equidigital number, since it uses as much as digits as its factorization.

19800155002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9900077503.

The product of its (nonzero) digits is 3600, while the sum is 31.

Adding to 19800155002 its reverse (20055100891), we get a palindrome (39855255893).

The spelling of 19800155002 in words is "nineteen billion, eight hundred million, one hundred fifty-five thousand, two".