661074437 has 4 divisors (see below), whose sum is σ = 661134336. Its totient is φ = 661014540.

The previous prime is 661074413. The next prime is 661074443. The reversal of 661074437 is 734470166.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 661074437 - 2²⁴ = 644297221 is a prime.

It is a super-2 number, since 2×661074437² = 874038822509733938, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 661074437.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661074637) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8063 + ... + 37244.

It is an arithmetic number, because the mean of its divisors is an integer number (165283584).

Almost surely, 2^661074437 is an apocalyptic number.

It is an amenable number.

661074437 is a deficient number, since it is larger than the sum of its proper divisors (59899).

661074437 is a wasteful number, since it uses less digits than its factorization.

661074437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59898.

The product of its (nonzero) digits is 84672, while the sum is 38.

The square root of 661074437 is about 25711.3678554837. The cubic root of 661074437 is about 871.1309715555.

The spelling of 661074437 in words is "six hundred sixty-one million, seventy-four thousand, four hundred thirty-seven".