212999940 has 36 divisors (see below), whose sum is σ = 646100364. Its totient is φ = 56799936.

The previous prime is 212999933. The next prime is 212999947. The reversal of 212999940 is 49999212.

It is an interprime number because it is at equal distance from previous prime (212999933) and next prime (212999947).

It can be written as a sum of positive squares in 2 ways, for example, as 163635264 + 49364676 = 12792^2 + 7026^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (212999947) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 591487 + ... + 591846.

Almost surely, 2^212999940 is an apocalyptic number.

212999940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212999940 is an abundant number, since it is smaller than the sum of its proper divisors (433100424).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

212999940 is a wasteful number, since it uses less digits than its factorization.

212999940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1183348 (or 1183343 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 45.

The square root of 212999940 is about 14594.5174637601. The cubic root of 212999940 is about 597.2092059066.

The spelling of 212999940 in words is "two hundred twelve million, nine hundred ninety-nine thousand, nine hundred forty".