213145749 has 14 divisors (see below), whose sum is σ = 319573526. Its totient is φ = 142096680.

The previous prime is 213145741. The next prime is 213145753. The reversal of 213145749 is 947541312.

It can be written as a sum of positive squares in only one way, i.e., 207878724 + 5267025 = 14418^2 + 2295^2 .

It is not a de Polignac number, because 213145749 - 2³ = 213145741 is a prime.

It is a super-2 number, since 2×213145749² = 90862220633542002, 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 (213145741) 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 13 ways as a sum of consecutive naturals, for example, 145462 + ... + 146919.

Almost surely, 2^213145749 is an apocalyptic number.

It is an amenable number.

213145749 is a deficient number, since it is larger than the sum of its proper divisors (106427777).

213145749 is an frugal number, since it uses more digits than its factorization.

213145749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292399 (or 292384 counting only the distinct ones).

The product of its digits is 30240, while the sum is 36.

The square root of 213145749 is about 14599.5119438973. The cubic root of 213145749 is about 597.3454479087.

The spelling of 213145749 in words is "two hundred thirteen million, one hundred forty-five thousand, seven hundred forty-nine".