625614991 has 4 divisors (see below), whose sum is σ = 627320032. Its totient is φ = 623909952.

The previous prime is 625614959. The next prime is 625615007. The reversal of 625614991 is 199416526.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 199416526 = 2 ⋅99708263.

It is a cyclic number.

It is not a de Polignac number, because 625614991 - 2⁵ = 625614959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (625614901) 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, 851970 + ... + 852703.

It is an arithmetic number, because the mean of its divisors is an integer number (156830008).

Almost surely, 2^625614991 is an apocalyptic number.

625614991 is a deficient number, since it is larger than the sum of its proper divisors (1705041).

625614991 is a wasteful number, since it uses less digits than its factorization.

625614991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1705040.

The product of its digits is 116640, while the sum is 43.

The square root of 625614991 is about 25012.2967957763. The cubic root of 625614991 is about 855.2683133596.

The spelling of 625614991 in words is "six hundred twenty-five million, six hundred fourteen thousand, nine hundred ninety-one".