61123021 has 4 divisors (see below), whose sum is σ = 61148412. Its totient is φ = 61097632.

The previous prime is 61123003. The next prime is 61123031. The reversal of 61123021 is 12032116.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8037225 + 53085796 = 2835^2 + 7286^2 .

It is a cyclic number.

It is not a de Polignac number, because 61123021 - 2¹¹ = 61120973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61122986 and 61123004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61123031) 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, 8656 + ... + 14041.

It is an arithmetic number, because the mean of its divisors is an integer number (15287103).

Almost surely, 2^61123021 is an apocalyptic number.

It is an amenable number.

61123021 is a deficient number, since it is larger than the sum of its proper divisors (25391).

61123021 is a wasteful number, since it uses less digits than its factorization.

61123021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25390.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 61123021 is about 7818.1213216475. The cubic root of 61123021 is about 393.9141700230.

Adding to 61123021 its reverse (12032116), we get a palindrome (73155137).

It can be divided in two parts, 611 and 23021, that added together give a palindrome (23632).

The spelling of 61123021 in words is "sixty-one million, one hundred twenty-three thousand, twenty-one".