61720619 has 4 divisors (see below), whose sum is σ = 61992744. Its totient is φ = 61448496.

The previous prime is 61720583. The next prime is 61720643. The reversal of 61720619 is 91602716.

It is a happy number.

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 61720619 - 2⁸ = 61720363 is a prime.

It is a super-2 number, since 2×61720619² = 7618869619486322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61720669) 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, 135722 + ... + 136175.

It is an arithmetic number, because the mean of its divisors is an integer number (15498186).

Almost surely, 2^61720619 is an apocalyptic number.

61720619 is a deficient number, since it is larger than the sum of its proper divisors (272125).

61720619 is a wasteful number, since it uses less digits than its factorization.

61720619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272124.

The product of its (nonzero) digits is 4536, while the sum is 32.

The square root of 61720619 is about 7856.2471320599. The cubic root of 61720619 is about 395.1937712955.

The spelling of 61720619 in words is "sixty-one million, seven hundred twenty thousand, six hundred nineteen".