61853551 has 4 divisors (see below), whose sum is σ = 63169632. Its totient is φ = 60537472.

The previous prime is 61853527. The next prime is 61853581. The reversal of 61853551 is 15535816.

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 61853551 - 2⁷ = 61853423 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 (61853521) 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, 657970 + ... + 658063.

It is an arithmetic number, because the mean of its divisors is an integer number (15792408).

Almost surely, 2^61853551 is an apocalyptic number.

61853551 is a deficient number, since it is larger than the sum of its proper divisors (1316081).

61853551 is a wasteful number, since it uses less digits than its factorization.

61853551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1316080.

The product of its digits is 18000, while the sum is 34.

The square root of 61853551 is about 7864.7028551624. The cubic root of 61853551 is about 395.4772866427.

The spelling of 61853551 in words is "sixty-one million, eight hundred fifty-three thousand, five hundred fifty-one".