661624214 has 4 divisors (see below), whose sum is σ = 992436324. Its totient is φ = 330812106.

The previous prime is 661624211. The next prime is 661624247. The reversal of 661624214 is 412426166.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×661624214² = 875493201102235592, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661624211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165406052 + ... + 165406055.

It is an arithmetic number, because the mean of its divisors is an integer number (248109081).

Almost surely, 2^661624214 is an apocalyptic number.

661624214 is a deficient number, since it is larger than the sum of its proper divisors (330812110).

661624214 is a wasteful number, since it uses less digits than its factorization.

661624214 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330812109.

The product of its digits is 13824, while the sum is 32.

The square root of 661624214 is about 25722.0569550726. The cubic root of 661624214 is about 871.3723942261.

The spelling of 661624214 in words is "six hundred sixty-one million, six hundred twenty-four thousand, two hundred fourteen".