61415551 has 4 divisors (see below), whose sum is σ = 61884504. Its totient is φ = 60946600.

The previous prime is 61415527. The next prime is 61415573. The reversal of 61415551 is 15551416.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61415551 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 (61415521) 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, 234280 + ... + 234541.

It is an arithmetic number, because the mean of its divisors is an integer number (15471126).

Almost surely, 2^61415551 is an apocalyptic number.

61415551 is a deficient number, since it is larger than the sum of its proper divisors (468953).

61415551 is a wasteful number, since it uses less digits than its factorization.

61415551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 468952.

The product of its digits is 3000, while the sum is 28.

The square root of 61415551 is about 7836.8074494656. The cubic root of 61415551 is about 394.5415843072.

Adding to 61415551 its reverse (15551416), we get a palindrome (76966967).

The spelling of 61415551 in words is "sixty-one million, four hundred fifteen thousand, five hundred fifty-one".