65400780 has 24 divisors (see below), whose sum is σ = 183122352. Its totient is φ = 17440192.

The previous prime is 65400749. The next prime is 65400787. The reversal of 65400780 is 8700456.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (65400787) 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, 544947 + ... + 545066.

It is an arithmetic number, because the mean of its divisors is an integer number (7630098).

Almost surely, 2^65400780 is an apocalyptic number.

65400780 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

65400780 is an abundant number, since it is smaller than the sum of its proper divisors (117721572).

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

65400780 is a wasteful number, since it uses less digits than its factorization.

65400780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1090025 (or 1090023 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 65400780 is about 8087.0748729068. The cubic root of 65400780 is about 402.8972557728.

The spelling of 65400780 in words is "sixty-five million, four hundred thousand, seven hundred eighty".