61515025 has 24 divisors (see below), whose sum is σ = 89619264. Its totient is φ = 41294400.

The previous prime is 61515019. The next prime is 61515031. The reversal of 61515025 is 52051516.

It is an interprime number because it is at equal distance from previous prime (61515019) and next prime (61515031).

It is not a de Polignac number, because 61515025 - 2¹¹ = 61512977 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5029 + ... + 12178.

It is an arithmetic number, because the mean of its divisors is an integer number (3734136).

Almost surely, 2^61515025 is an apocalyptic number.

61515025 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

61515025 is a deficient number, since it is larger than the sum of its proper divisors (28104239).

61515025 is a wasteful number, since it uses less digits than its factorization.

61515025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17241 (or 17236 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 25.

The square root of 61515025 is about 7843.1514711881. The cubic root of 61515025 is about 394.7544807635.

The spelling of 61515025 in words is "sixty-one million, five hundred fifteen thousand, twenty-five".