211145405 has 8 divisors (see below), whose sum is σ = 264390912. Its totient is φ = 161572048.

The previous prime is 211145401. The next prime is 211145411. The reversal of 211145405 is 504541112.

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

It is a cyclic number.

It is not a de Polignac number, because 211145405 - 2² = 211145401 is a prime.

It is a super-2 number, since 2×211145405² = 89164764105228050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211145401) 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, 917909 + ... + 918138.

It is an arithmetic number, because the mean of its divisors is an integer number (33048864).

Almost surely, 2^211145405 is an apocalyptic number.

It is an amenable number.

211145405 is a deficient number, since it is larger than the sum of its proper divisors (53245507).

211145405 is a wasteful number, since it uses less digits than its factorization.

211145405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1836075.

The product of its (nonzero) digits is 800, while the sum is 23.

The square root of 211145405 is about 14530.8432308659. The cubic root of 211145405 is about 595.4709027826.

Adding to 211145405 its reverse (504541112), we get a palindrome (715686517).

The spelling of 211145405 in words is "two hundred eleven million, one hundred forty-five thousand, four hundred five".