1201320999 has 18 divisors (see below), whose sum is σ = 1831381656. Its totient is φ = 758727000.

The previous prime is 1201320943. The next prime is 1201321061. The reversal of 1201320999 is 9990231021.

It is a happy number.

It is not a de Polignac number, because 1201320999 - 2⁷ = 1201320871 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1201320919) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 181627 + ... + 188124.

Almost surely, 2^1201320999 is an apocalyptic number.

1201320999 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1201320999 is a deficient number, since it is larger than the sum of its proper divisors (630060657).

1201320999 is a wasteful number, since it uses less digits than its factorization.

1201320999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 369795 (or 369773 counting only the distinct ones).

The product of its (nonzero) digits is 8748, while the sum is 36.

The square root of 1201320999 is about 34660.0778850827. The cubic root of 1201320999 is about 1063.0483625483.

The spelling of 1201320999 in words is "one billion, two hundred one million, three hundred twenty thousand, nine hundred ninety-nine".