61655615 has 16 divisors (see below), whose sum is σ = 84870720. Its totient is φ = 42120960.

The previous prime is 61655603. The next prime is 61655623. The reversal of 61655615 is 51655616.

It is not a de Polignac number, because 61655615 - 2¹⁶ = 61590079 is a prime.

It is a super-2 number, since 2×61655615² = 7602829722056450, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6701 + ... + 12969.

It is an arithmetic number, because the mean of its divisors is an integer number (5304420).

Almost surely, 2^61655615 is an apocalyptic number.

61655615 is a deficient number, since it is larger than the sum of its proper divisors (23215105).

61655615 is a wasteful number, since it uses less digits than its factorization.

61655615 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6562.

The product of its digits is 27000, while the sum is 35.

The square root of 61655615 is about 7852.1089523771. The cubic root of 61655615 is about 395.0549835333.

Subtracting from 61655615 its reverse (51655616), we obtain a palindrome (9999999).

The spelling of 61655615 in words is "sixty-one million, six hundred fifty-five thousand, six hundred fifteen".