61528731 has 8 divisors (see below), whose sum is σ = 89496384. Its totient is φ = 37290120.

The previous prime is 61528723. The next prime is 61528757. The reversal of 61528731 is 13782516.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61528731 - 2³ = 61528723 is a prime.

It is a super-2 number, since 2×61528731² = 7571569476940722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 1864507 = 61528731 / (6 + 1 + 5 + 2 + 8 + 7 + 3 + 1).

It is a junction number, because it is equal to n+sod(n) for n = 61528692 and 61528701.

It is not an unprimeable number, because it can be changed into a prime (61528711) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 932221 + ... + 932286.

It is an arithmetic number, because the mean of its divisors is an integer number (11187048).

Almost surely, 2^61528731 is an apocalyptic number.

61528731 is a deficient number, since it is larger than the sum of its proper divisors (27967653).

61528731 is a wasteful number, since it uses less digits than its factorization.

61528731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1864521.

The product of its digits is 10080, while the sum is 33.

The square root of 61528731 is about 7844.0251784400. The cubic root of 61528731 is about 394.7837966535.

The spelling of 61528731 in words is "sixty-one million, five hundred twenty-eight thousand, seven hundred thirty-one".