61821369 has 12 divisors (see below), whose sum is σ = 90631216. Its totient is φ = 40598712.

The previous prime is 61821349. The next prime is 61821379. The reversal of 61821369 is 96312816.

61821369 is a `hidden beast` number, since 618 + 2 + 1 + 36 + 9 = 666.

It is not a de Polignac number, because 61821369 - 2¹⁹ = 61297081 is a prime.

It is a super-2 number, since 2×61821369² = 7643763330068322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61821329) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 50659 + ... + 51864.

Almost surely, 2^61821369 is an apocalyptic number.

It is an amenable number.

61821369 is a deficient number, since it is larger than the sum of its proper divisors (28809847).

61821369 is a wasteful number, since it uses less digits than its factorization.

61821369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102596 (or 102593 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 61821369 is about 7862.6566121127. The cubic root of 61821369 is about 395.4086866578.

The spelling of 61821369 in words is "sixty-one million, eight hundred twenty-one thousand, three hundred sixty-nine".