61511091 has 4 divisors (see below), whose sum is σ = 82014792. Its totient is φ = 41007392.

The previous prime is 61511089. The next prime is 61511101. The reversal of 61511091 is 19011516.

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

It is a cyclic number.

It is not a de Polignac number, because 61511091 - 2¹ = 61511089 is a prime.

It is a super-2 number, since 2×61511091² = 7567228632020562, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61511011) 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, 10251846 + ... + 10251851.

It is an arithmetic number, because the mean of its divisors is an integer number (20503698).

Almost surely, 2^61511091 is an apocalyptic number.

61511091 is a deficient number, since it is larger than the sum of its proper divisors (20503701).

61511091 is a wasteful number, since it uses less digits than its factorization.

61511091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20503700.

The product of its (nonzero) digits is 270, while the sum is 24.

The square root of 61511091 is about 7842.9006751329. The cubic root of 61511091 is about 394.7460654902.

The spelling of 61511091 in words is "sixty-one million, five hundred eleven thousand, ninety-one".