61156551 has 4 divisors (see below), whose sum is σ = 81542072. Its totient is φ = 40771032.

The previous prime is 61156477. The next prime is 61156561. The reversal of 61156551 is 15565116.

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

It is not a de Polignac number, because 61156551 - 2¹³ = 61148359 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61156561) 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, 10192756 + ... + 10192761.

It is an arithmetic number, because the mean of its divisors is an integer number (20385518).

Almost surely, 2^61156551 is an apocalyptic number.

61156551 is a deficient number, since it is larger than the sum of its proper divisors (20385521).

61156551 is a wasteful number, since it uses less digits than its factorization.

61156551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20385520.

The product of its digits is 4500, while the sum is 30.

The square root of 61156551 is about 7820.2654047033. The cubic root of 61156551 is about 393.9861861391.

The spelling of 61156551 in words is "sixty-one million, one hundred fifty-six thousand, five hundred fifty-one".