61421553 has 6 divisors (see below), whose sum is σ = 88720034. Its totient is φ = 40947696.

The previous prime is 61421453. The next prime is 61421573. The reversal of 61421553 is 35512416.

It can be written as a sum of positive squares in only one way, i.e., 54066609 + 7354944 = 7353^2 + 2712^2 .

It is not a de Polignac number, because 61421553 - 2¹⁶ = 61356017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (61421573) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3412300 + ... + 3412317.

Almost surely, 2^61421553 is an apocalyptic number.

It is an amenable number.

61421553 is a deficient number, since it is larger than the sum of its proper divisors (27298481).

61421553 is a wasteful number, since it uses less digits than its factorization.

61421553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6824623 (or 6824620 counting only the distinct ones).

The product of its digits is 3600, while the sum is 27.

The square root of 61421553 is about 7837.1903766592. The cubic root of 61421553 is about 394.5544364345.

Adding to 61421553 its reverse (35512416), we get a palindrome (96933969).

The spelling of 61421553 in words is "sixty-one million, four hundred twenty-one thousand, five hundred fifty-three".