612999981 has 40 divisors (see below), whose sum is σ = 1003308768. Its totient is φ = 369900000.

The previous prime is 612999953. The next prime is 613000001. The reversal of 612999981 is 189999216.

It is not a de Polignac number, because 612999981 - 2⁵ = 612999949 is a prime.

It is a super-2 number, since 2×612999981² = 751537953412000722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (612999181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 222271 + ... + 225011.

Almost surely, 2^612999981 is an apocalyptic number.

It is an amenable number.

612999981 is a deficient number, since it is larger than the sum of its proper divisors (390308787).

612999981 is a wasteful number, since it uses less digits than its factorization.

612999981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3015 (or 3006 counting only the distinct ones).

The product of its digits is 629856, while the sum is 54.

The square root of 612999981 is about 24758.8364225785. The cubic root of 612999981 is about 849.4806428253.

The spelling of 612999981 in words is "six hundred twelve million, nine hundred ninety-nine thousand, nine hundred eighty-one".