1661337356 has 36 divisors (see below), whose sum is σ = 3396137976. Its totient is φ = 709027200.

The previous prime is 1661337329. The next prime is 1661337397. The reversal of 1661337356 is 6537331661.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29651 + ... + 64821.

It is an arithmetic number, because the mean of its divisors is an integer number (94337166).

Almost surely, 2^1661337356 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 1661337356, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1698068988).

1661337356 is an abundant number, since it is smaller than the sum of its proper divisors (1734800620).

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

1661337356 is a wasteful number, since it uses less digits than its factorization.

1661337356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35430 (or 35421 counting only the distinct ones).

The product of its digits is 204120, while the sum is 41.

The square root of 1661337356 is about 40759.5063267454. The cubic root of 1661337356 is about 1184.3660328531.

The spelling of 1661337356 in words is "one billion, six hundred sixty-one million, three hundred thirty-seven thousand, three hundred fifty-six".