63698440 has 32 divisors (see below), whose sum is σ = 154347480. Its totient is φ = 23519232.

The previous prime is 63698429. The next prime is 63698539. The reversal of 63698440 is 4489636.

63698440 = 391² + 392² + ... + 630².

It can be written as a sum of positive squares in 4 ways, for example, as 37871716 + 25826724 = 6154^2 + 5082^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 63698393 and 63698402.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 60729 + ... + 61768.

Almost surely, 2^63698440 is an apocalyptic number.

It is an amenable number.

63698440 is an abundant number, since it is smaller than the sum of its proper divisors (90649040).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

63698440 is a wasteful number, since it uses less digits than its factorization.

63698440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122521 (or 122517 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 40.

The square root of 63698440 is about 7981.1302457735. The cubic root of 63698440 is about 399.3707606637.

The spelling of 63698440 in words is "sixty-three million, six hundred ninety-eight thousand, four hundred forty".