25021978 has 4 divisors (see below), whose sum is σ = 37532970. Its totient is φ = 12510988.

The previous prime is 25021973. The next prime is 25021979. The reversal of 25021978 is 87912052.

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

It can be written as a sum of positive squares in only one way, i.e., 13712209 + 11309769 = 3703^2 + 3363^2 .

It is not an unprimeable number, because it can be changed into a prime (25021973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6255493 + ... + 6255496.

Almost surely, 2^25021978 is an apocalyptic number.

25021978 is a deficient number, since it is larger than the sum of its proper divisors (12510992).

25021978 is a wasteful number, since it uses less digits than its factorization.

25021978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12510991.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 25021978 is about 5002.1973171797. The cubic root of 25021978 is about 292.4874341401.

The spelling of 25021978 in words is "twenty-five million, twenty-one thousand, nine hundred seventy-eight".