661292424 has 192 divisors, whose sum is σ = 2025354240. Its totient is φ = 200931840.

The previous prime is 661292407. The next prime is 661292459. The reversal of 661292424 is 424292166.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 3462169 + ... + 3462359.

It is an arithmetic number, because the mean of its divisors is an integer number (10548720).

Almost surely, 2^661292424 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661292424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1012677120).

661292424 is an abundant number, since it is smaller than the sum of its proper divisors (1364061816).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661292424 is a wasteful number, since it uses less digits than its factorization.

661292424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362 (or 346 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

The square root of 661292424 is about 25715.6066232162. The cubic root of 661292424 is about 871.2267118372.

Adding to 661292424 its product of digits (41472), we get a triangular number (661333896 = T₃₆₃₆₈).

The spelling of 661292424 in words is "six hundred sixty-one million, two hundred ninety-two thousand, four hundred twenty-four".