1216425999 has 8 divisors (see below), whose sum is σ = 1707264640. Its totient is φ = 768269016.

The previous prime is 1216425997. The next prime is 1216426009. The reversal of 1216425999 is 9995246121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1216425999 - 2¹ = 1216425997 is a prime.

It is a super-2 number, since 2×1216425999² = 2959384422086296002, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216425997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10670347 + ... + 10670460.

It is an arithmetic number, because the mean of its divisors is an integer number (213408080).

Almost surely, 2^1216425999 is an apocalyptic number.

1216425999 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1216425999 is a deficient number, since it is larger than the sum of its proper divisors (490838641).

1216425999 is a wasteful number, since it uses less digits than its factorization.

1216425999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21340829.

The product of its digits is 349920, while the sum is 48.

The square root of 1216425999 is about 34877.2991930281. The cubic root of 1216425999 is about 1067.4852870892.

The spelling of 1216425999 in words is "one billion, two hundred sixteen million, four hundred twenty-five thousand, nine hundred ninety-nine".