213658749 has 32 divisors (see below), whose sum is σ = 325946880. Its totient is φ = 138240000.

The previous prime is 213658691. The next prime is 213658769. The reversal of 213658749 is 947856312.

213658749 is a `hidden beast` number, since 21 + 3 + 6 + 587 + 49 = 666.

It is not a de Polignac number, because 213658749 - 2¹² = 213654653 is a prime.

It is a super-2 number, since 2×213658749² = 91300122048490002, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213658769) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 284124 + ... + 284874.

It is an arithmetic number, because the mean of its divisors is an integer number (10185840).

Almost surely, 2^213658749 is an apocalyptic number.

It is an amenable number.

213658749 is a deficient number, since it is larger than the sum of its proper divisors (112288131).

213658749 is a wasteful number, since it uses less digits than its factorization.

213658749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1058 (or 1052 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 213658749 is about 14617.0704657260. The cubic root of 213658749 is about 597.8242950495.

The spelling of 213658749 in words is "two hundred thirteen million, six hundred fifty-eight thousand, seven hundred forty-nine".