61620121 has 8 divisors (see below), whose sum is σ = 65313864. Its totient is φ = 57934080.

The previous prime is 61620109. The next prime is 61620127. The reversal of 61620121 is 12102616.

It can be written as a sum of positive squares in 4 ways, for example, as 29539225 + 32080896 = 5435^2 + 5664^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61620121 - 2⁹ = 61619609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61620127) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27711 + ... + 29851.

It is an arithmetic number, because the mean of its divisors is an integer number (8164233).

Almost surely, 2^61620121 is an apocalyptic number.

It is an amenable number.

61620121 is a deficient number, since it is larger than the sum of its proper divisors (3693743).

61620121 is a wasteful number, since it uses less digits than its factorization.

61620121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3851.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 61620121 is about 7849.8484698751. The cubic root of 61620121 is about 394.9791603597.

Adding to 61620121 its reverse (12102616), we get a palindrome (73722737).

The spelling of 61620121 in words is "sixty-one million, six hundred twenty thousand, one hundred twenty-one".